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  Library of Congress Cataloging In Publication Data

  Beaumont, Greg, 1943-
  Many-storied mountains.

  (Natural history series)
  1. Natural history--Montana--Glacier National Park.
  2. Glacier National Park. I. Title. II. Series: Natural history series
              (Washington, D.C.)
  OH105 M9B43    500.9'786'52    78-606071

                         Many-storied Mountains
                   The Life of Glacier National Park

                              Written and
                            photographed by
                             Greg Beaumont

                                  1978
                         Natural History Series
                        Division of Publications
                         National Park Service
                    U.S. Department of the Interior

    [Illustration: The landform of Glacier National Park is a monument
    to the power of moving ice. This view from Stoney Indian Pass  is
    startlingly different from the scene of a million years ago, when
    the glaciers of the Pleistocene were sculpturing the land. Only the
    higher peaks would then have been visible above the blanket of ice
    that flowed like a slow-moving river down into the Mokowanis Valley
    and out into the Great Plains beyond.]

About This Book

This natural history of the mountain wilderness called Glacier National
Park is not a guidebook, but provides an overview of the ecology of the
region. At the same time, it is a personal statement, revealing one
individual's response to this rugged, delicate land.

For their consistent cooperation and helpfulness, I wish especially to
thank Chief Naturalist Ed Rothfuss and his capable staff. Technical and
field assistance came from many; for special thanks, I would like to
single out Art Sedlack, Francis Singer, Bert Gildart, Walt Martin, Craig
Kuchel, and Danny On. The manuscript profited greatly from the criticism
of Douglas Chadwick, to whom I am deeply grateful.

                                                                  --G.B.

The National Park Service Division of Publications gratefully
acknowledges the financial support given this book project by the
Glacier Natural History Association, Inc., West Glacier, Mont.

                                Contents

  Song of the High Peaks                                                1
  Cycles and Seasons                                                    5
      Bedrock: The First Story                                          6
      The Rising of the Sun and the Running of the Deer: A Glacier
          Year                                                         39
  Plant-and-Animal Communities                                         43
      Over Going-to-the-Sun Road                                       44
      Groves and Grasslands: The Prairie Sea                           46
      The Forest                                                       70
      Scrub Forest                                                    105
      Tundra                                                          109
      Water Communities                                               114
  Shooting Stars                                                      121
  Appendix                                                            125
  Pictorial Features
      The Mountains of Glacier                                         10
      The Forests of Glacier                                           48
      The Vital Predator                                               78
      Protective Coloration                                            84
      _Ursus arctos horribilus:_ The Vulnerable King                   88
      Bald Eagles and Kokanee Salmon: A Recent Gathering               92
      A Triumph of Many Colors                                         96
      Fire Succession: Key to Continuity                              100

Illustrations by Celia Strain/Morgan-Burchette Assoc.

    [Illustration: Soaring eagle]

                             Song of the High Peaks

April again and the wind turns on the Great Plains. Wedges of geese,
high and determined, began this storm of spring, their voices sharp as
the morning frost. Sicklebills cry to claim the land, sandhill cranes
wheel and talk overhead, and everywhere the killdeer shout.
Pasqueflowers push the bleak soil aside, beginning the westward rush
that I must join, seeking again the sight of mountains.

In Glacier National Park the land is folded up. On the east, Chief
Mountain, Curly Bear, and Rising Wolf break the prairie's hold. When the
early French fur trappers saw these peaks glistening in the distance
with summer-long snows and perpetual ice, they named this region "the
land of shining mountains." But for all the ice and snow that reflect
the summer sun, the park's present glaciers are but snowflakes compared
to the mighty rivers of ice that carved this land. Glaciation, the
magnificent sculptor, left its bold signature everywhere, and this park
honors with its name the force that shaped it.

But the essential excitement of this land is more than cliff face,
spire, and sudden storm. It comes to you when you realize that here is
an aggregation of dramatically differing life zones, where a day's walk
can easily take you from prairie and forest to treelimit and tundra;
where a dense forest of redcedar and hemlock, similar to the rain
forests of the Pacific coast, exists a score of kilometers from the
great prairie sea.

Or it comes when you discover that these mountains--young and sharp with
shadows, snow-jeweled and newly gowned with forests--are chiseled from
the oldest unaltered sedimentary rocks on earth.

I come from the prairie and love its broad strokes; I've learned to hear
the singing in the grass and to see those long, slow seasons soar the
level horizons like gliding hawks. But here I learned to match my days
against a wild earth, and in me grew the mysterious need to know a
mountain from its every side. Mountains that wear the dawn like yellow
hats, repeated in the named and nameless lakes. Mountains that stretch
the storms between them and balance rainbows ridge to ridge.

I must see again the secret forest places, where the paleflowered
wood-nymphs hover like a breath, and know once more the endless meadows
painted camas blue.

I need the perfect freedom of this land, to be able to say, _today I
will climb Siyeh_: to stand, for a time, on the rugged shoulders of this
upright earth.

    [Illustration: The sharp spire of little Matterhorn and the broad
    face of Mt. Edwards loom above Going-to-the-Sun Road in the upper
    McDonald Valley. During warm days in spring the valleys of the park
    resound with the thunder of avalanches.]

    [Illustration: Twilight view.]

                               Cycles and Seasons

Bedrock: The First Story

On the trail that connects the Logan Pass visitor center to Hidden Lake
overlook there is a shallow pond. Near Hidden Pass, it collects its
meltwater from the Continental Divide and sends it down the shallow
gorge that drains the Hanging Gardens; as a waterfall it plunges into
the upper St. Mary Valley where it becomes Reynolds Creek; joined by
other tributaries, it continues its long journey to Hudson Bay.

The surface of this pond is seldom still, for the wind treats it like a
sea. Because the water is shallow, the wave action wrinkles the bottom
mud into ripple patterns, mimicking the churning waves.

I like to come here early in the morning. Sometimes, arriving before the
wind awakes, I catch reflections of the surrounding mountains. Beyond
the low bench of Logan Pass the Garden Wall begins, running northward
with the Divide. In the eastern valley the pitched peak of
Going-to-the-Sun hunkers in the morning light like a tensed warrior. To
the south, the incisor Bearhat, beautiful cloud cutter of Hidden Lake
Valley, juts above the nearby saddle of the pass. But over this place,
standing as fresh monuments to an age of ice, tower the cliffs of
Clements and the pyramid Reynolds.

I am sitting on a wedge of red rock. Its surface exhibits a wrinkled
pattern identical to the ripples in the soft mud of the shallow pond.
The distance is not great; with a stick I could reach out and touch the
mud. Yet this represents a gulf no bird can fly, for between the ripples
of this rock and the ripples of this mud lie billions of vanished
mornings, a constellation of years.

These red, green, tan, white, black and purple bands of rock that layer
Glacier's mountains comprise the oldest unaltered sedimentary rocks on
Earth. They were laid down in Precambrian time, more than a billion
years ago, when life was just beginning, as the deposits of an inland
sea.

For millions of years, sand, mud and carbonates washed into the ancient
sea, compressing the lower layers into mudstones and limestones,
building up a sediment thickness that may have been as much as 10,000
meters (_see_ metric conversion table on page 136).

When we look at the sharp contours of Glacier's mountains, we see the
evidence of uplift, overthrust and glaciation. But on the geologic clock
these are recent events, a mere eyeblink of time ago. For the vast
majority of years, the rocks lay undisturbed and level beneath the sea
and land.

To understand better the tremendous time scale these rocks represent, we
need a way to visualize the vast collection of years. If we were to make
a movie of these geologic events, we would first need to determine how
many years each minute should represent. Since the Pleistocene lasted
about 3,000,000 years (its four ice ages sculpting the present muscle of
this land), let us make each minute portray a million years. To
chronicle these rocks we will then need a film 60 hours long!

Not until the fifty-seventh hour of our film will the Mesozoic lowlands
begin to bulge with the coming Rocky Mountain chain. During the long
preceding hours we would have seen little else but sea--withdrawing,
advancing, deep and shallow; yellow, green, and brown with great
colonies of algae. Unseen below the water, lava has spilled out
occasionally on the sea bottom; once, it intruded between the rock
layers below, forming the conspicuous, 60-meter-thick band of black
diorite that we see today on many mountain faces in Glacier.

During this time of initial uplift an amazing process is going on deep
underground. A major fault has developed, fracturing the buckled layers
of rock. A vast mountain plate begins to slide eastward, over-riding and
submerging the rock layers to the east and opening the wide trench that
is today the North Fork Valley. Known as the Lewis Overthrust, this
gigantic earth-force has created an unusual situation: ancient rock
strata lying atop recent rock strata.

Now less than 3 minutes of film remain. The arrival of the ice is
imminent. We look at the landscape of featureless mountains and wonder
at the dramatic difference that this last 3 million years will make. We
do not see the familiar forests and lakes, the savage peaks, and the
broad, deep valleys of this present land. These mountains are gentle,
arid, and shallow-valleyed. The vague outlines are there; we recognize
the general alignments of the drainage systems, the bloated domes from
which sharp peaks will be cut. The mountains are connected to one
another by blunt ridges and smooth saddles, and the shadows they cast
are dull, dunelike.

Suddenly the ice is there, filling the landscape, with only the
mountaintops protruding. Four times in these last 3 minutes of film the
ice sheets advance and retreat, each time leaving an altered landscape.
Strange lakes and forests fill the gaps between the glacial invasions.
Then we see the mountains we now know come into being rapidly, as if the
land were being hacked into shape by giant cleavers.

After this flicker of Pleistocene time, the film ends, the forests
return, and familiar lakes shine beneath the sun again--these lakes and
forests we had thought to be timeless.

[_]
Up springs the morning wind from Hidden Valley, making the nearby alpine
fir branches whiz with its passing and shattering the perfect reflection
of Bearhat Peak on the pond. From where I sit, it is a short distance to
Hidden Pass; so I leave the pond and walk to the overlook to see again
the fine basin quarried by an ancient glacier.

Hidden Lake, deep, far below, so blue, fits into its cliffed, crooked
valley like a polished boomerang. Closely ringed by ridge and
peak--distant Sperry Glacier and pointed Gunsight peering up from the
southern jumble, and broad Bearhat impossibly close--this lovely lake is
almost lost amid such sharp proclamations of rock. Its outlet gorge
gives a narrow view across the angled, hidden valleys of Avalanche and
McDonald, past the pyramid of Stanton, to the low, faraway undulations
of the Whitefish Range.

Glaciation is a cruel master of mountains, biting deeply into their bulk
and leaving sheer, spectacular contours when the glaciers disappear. The
landforms here attest to their power, everywhere exhibiting the effects
of glaciation.

In eating back the mountain headwall, alpine glaciers formed rounded
depressions, called cirques. Unlike the narrow clefts left by running
water, these broad, deep basins look as though they were made by
ice-cream scoops gouging into the rock. Hidden, Ptarmigan, Iceberg, and
Avalanche Lakes sit in well-developed cirque basins, and many mountains
are dimpled by the beginnings of other cirques--the conspicuous
amphitheater on the south shoulder of Heaven's Peak, for example.

Occupying all major drainage systems, glaciers modified the contour of
the valleys, changing them from their narrow, stream-cut V-shapes into
broad U-shapes. Into these wide main valleys, waterfalls plunge from
higher, smaller valleys. Like rivers, flowing glaciers have tributaries.
Lacking the ice mass and cutting power of the main glaciers, these
tributary ice fingers could not bite as deeply into the bedrock. When
the ice melted, hanging valleys were left stranded high above the main
valley floor. Hidden Lake sits in one of these hanging valleys, and from
it Hidden Creek plunges 750 meters into Avalanche Basin toward McDonald
Creek.

On my many previous visits to this pass I have been too busy enjoying
the wildflowers, the weather, or the scenery to realize what an open
textbook of glaciation is everywhere displayed.

I stand here on a small saddle of a pass. Wherever glaciers met, passes,
or cols, were created. A high, notched pass like this one (or
Swiftcurrent or Gunsight) reveals recent connections. Broad, lower
passes, such as Logan, resulted where the ice early overran the mountain
ridge and had a chance to work longer.

Where two glaciers worked on opposing sides of a ridge and failed to
meet, they formed an arête--a thin, steep-walled remnant resembling a
saw blade. Another ice age would probably consume the park's many thin
arêtes, such as the Garden Wall and Ptarmigan Wall; but it would also
create new ones from existing ridges.

Further testimony to the sculpting power of ice is presented by Mt.
Reynolds, looming to the east. The most dramatic feature of a glaciated
landscape is the pyramid-shaped mountain called a horn--and Reynolds is
a perfect example. Horns were formed when three or more glaciers cloaked
the mountain, excavating its sides toward its core and gradually
transforming its original domed shape into a sheer-sided peak. Glacier
has many remarkable horns, from the sleek spire of St. Nicholas in the
south to exquisite Kinnerly in the northern Kintla valley.

Sperry Glacier stares back at me from the flank of Gunsight. Glaciers
found in the park today are not remnants of the last ice phase, which
ended here about 8,000 years ago, but are newly formed, having come into
existence some 4,000 years ago. They reflect a cooling trend in the
present climate.

Shrinking steadily from their period of greatest extent in the middle of
the last century, these modern glaciers finally stabilized in the late
1940s and since then have shown only a slight increase in area.

Movement distinguishes glaciers from icefields, and the movement of ice
is a force on as well as a feature of a landscape. A glacier excavates
by abrading and plucking at the rock. Alternately melting and freezing,
ice at the headwalls plucks out blocks of rock. Ultimately the rocks are
deposited along the sides or at the feet of the glacier as moraine
debris. But as they move in the grip of the ice, they constantly abrade
the rock surfaces they encounter. Polished rock beds of past glaciers
show striations--grooves gouged by rock fragments imbedded in the moving
ice.

Flow rate of a glacier depends upon the thickness of the ice and the
degree of slope. Under tremendous pressure, ice becomes plastic, like
thick taffy. Unlike kilometer-thick continental glaciers, which may move
a hundred meters a day, small alpine glaciers seldom progress more than
two or three centimeters per day.

Although a glacier moves, it gets nowhere if in a state of
equilibrium--when annual melting equals annual accumulation. Snow mass
gained at the sun-shielded headwall is usually lost as melt at the
exposed snout. Glaciers such as Sexton or Weasel Collar, whose snouts
perch on cliff edges, also lose mass by calving. Thunder you hear on a
late-summer day near such a glacier may actually be the sound of ice
pushed off from the lip of a cliff.

Walking back to the visitor center, I suddenly stop where the trail
skirts the steep moraine of Mt. Clements. From the opposite side of the
moraine five mountain goats have appeared. Spotting me on the trail
below, they also halt. But before I can get to my camera they are off in
a stiff-legged gallop, running in single file along the crest of the
moraine to the distant safety of the mountain face.

Moraines are ridges of rock debris piled up along the edges and
terminuses of glaciers. Like a bracelet lying against the wall of this
mountain, the circle of steeply piled debris marks the extent of a
small, recently vanished glacier. Ghost of the power that once resided
here, a stagnant icefield lies beneath the confining walls of the
moraine. The recent accumulation of these rock fragments is a mighty
accomplishment, attesting to the force of moving ice.

                                                     _continued on p. 38_

    [Illustration: The Mountains of Glacier

    Lying astride the Continental Divide in the Northern Rockies,
    Glacier is above all else a mountain park. The special beauty of its
    lakes, streams, and forests derives from the microclimates and
    varied topography and soil produced by mountain-building and
    mountain-eroding forces.]

    [Illustration: Overthrust Mountains

    1 A hypothetical block of the Earth's crust in the region of Glacier
    National Park as it existed more than 60 million years ago. The two
    layers shown actually represent many strata of sedimentary rocks.

    2 Lateral pressure begins to force the rock layers to buckle.

    3 A large fold has been created, forcing the rock strata to double
    over and overturning some layers. A break, or _fault_, is forming at
    the plane of greatest stress.

    4 The break has been completed and the strata west of the fault have
    slid eastward, up and over the rocks east of the fault.

    5 The Glacier landscape today. Throughout the millions of years
    during which the folding, faulting, and overthrusting have been
    taking place, the process of erosion has continued; a thousand
    meters of stratified rocks have been worn away, so that only a
    remnant of the overthrust layers can be seen today. Because
    Glacier's eastern slope represents the eroded face of the overthrust
    block, the mountain range rises precipitously from the prairie, with
    no foothills breaking the abrupt transition from open prairie to
    mountain valley.]

    [Illustration: The peaks in this photograph (a view to the northwest
    from Marias Pass) are remnants of the overthrust block, which moved
    eastward. The dividing line between the light-colored rocks and the
    gray talus slopes beneath them is the Lewis Overthrust Fault.]

    [Illustration: Glaciation

    1 This is how the landscape in this region might have appeared
    before the onset of the Pleistocene, millions of years ago. Note the
    stream-eroded, V-shaped valleys. The climate at that time was dry.

    2 Glaciers began to form high on the peaks, crept downward, and
    joined to form larger glaciers.

    3 After many centuries of glaciation, tributary glaciers have cut
    back into the peaks, forming basins called _cirques_. Thick
    glaciers, moving rapidly and carrying rock fragments, have abraded
    the main valleys' floors and sides, widening and deepening the
    valleys into characteristic U-shapes.]

  V-shaped Valley
  Tributary Glacier
  Unglaciated Peak
  Headwall
  Meltwater Stream
  Nose of Glacier
  Crevasse

    [Illustration: 4 In the present landscape, free of all but remnant
    glaciers, small lakes called _tarns_ occupy many of the cirque
    basins; and waterfalls plunge into the main valleys from higher,
    shallower, tributary valleys, called _hanging valleys_. _Alluvial
    cones_--recent accumulations of rock debris--have begun to build
    along the valley walls. In the main valley, a _moraine_ (a deposit
    of rock materials left by the retreating glacier) has formed a dam
    that holds back a large lake.

    During all this time, all parts of the terrain not buried under ice
    and snow have been weathered and eroded by nonglacial forces. Thus
    the contours of the jagged peaks and sheer cliffs have been
    softened.]

  Unglaciated V-shaped Valley
  U-shaped Valley
  Hanging Valley
  Cirque
  Tarn
  Alluvial Cone
  Moraine
  Morainal Lake

    [Illustration: Glacial landforms can be identified in this view of
    the Mokowanis Valley.]

    [Illustration: A Divided Climate

    Because of an eastward flow of cool, moist Pacific air masses, the
    climate of northwestern Montana, including the western portion of
    Glacier National Park, differs from that of other portions of
    Montana. As a result of increased precipitation, Glacier's western
    valleys support a rich flora, more typical of the Pacific Northwest.

    West

    Moist Pacific air

    As the moisture-laden Pacific winds are pushed up the windward
    slopes of Glacier's mountains, the air cools and water vapor
    condenses, forming fog or clouds. Rain or snow begins to fall as the
    air continues to rise and cool. By the time the air mass reaches the
    crest and flows down the leeward slopes, most of the moisture has
    been lost.

    Western slopes average about 70 cm. of precipitation at elevations
    between 900 and 1,100 m. Upper elevations average 200 to 250 cm.,
    mostly in the form of snow; and 300 to 500 cm. is common.

    East

    Dry chinook winds

    Eastern slopes, under the influence of Continental air masses,
    receive less annual precipitation. West Glacier's annual average is
    66.5 cm. Babb, a small town east of the park, averages 49.3 cm.
    Frequent high winds east of the Divide further reduce moisture
    through evaporation.

    Exposed to Arctic air masses flowing down from Canada, locations
    east of the Divide also suffer more severe winter conditions than do
    protected western valleys. Average January temperature is -5°C at
    West Glacier, -8° at Babb.

    Moreover, 80 percent of the winter days in the western portion of
    the park are overcast, a condition almost identical to that of
    Seattle, Wash. This serves to moderate winter temperatures and to
    minimize evaporation.]

    [Illustration: Moss campion and mountain forget-me-not colonize a
    fellfield. Fellfields are rocky alpine sites that are slightly less
    than 50% bare rock, interspersed with such plant pioneers as cushion
    plants, mosses, and lichens.]

    [Illustration: High lakes generally occupy cirque basins. These
    depressions in the valley bedrock, quarried by glaciers, are deepest
    near the headwall where ice thickness was greatest. Cold and deep,
    and ice-free only weeks each year, tarns cannot support vascular
    plants or vertebrates. Iceberg Lake, shut off from the sun most of
    the year by the encompassing 1,000-meter walls of Mt. Wilbur and the
    Ptarmigan Wall, is never completely free of ice.]

    [Illustration: Lake McDonald, 16 kilometers long, 2 kilometers wide,
    and 134 meters deep, is the largest lake in the park. Its basin is
    the classic U-shaped glacial valley. Forested lateral moraines on
    either shore gently rise 600 meters above lake level.
    Going-to-the-Sun Road snakes along the eastern shore, and Logan Pass
    lies near the center of the photograph, behind the peaks of the
    Lewis Range.]

    [Illustration: Subjected to the drying and shaping effects of wind
    both winter and summer, this Douglas-fir, growing in the prairie
    community near St. Mary, will attain neither the symmetrical shape
    nor the great size of the Douglas-firs growing in moister, more
    sheltered sites on the western slopes of the Continental Divide.]

    [Illustration: Freeze-and-thaw cycles continually fracture and
    loosen rocks along joints, making them subject to removal by the
    actions of water, gravity, and avalanche. The resulting fans of rock
    debris (talus cones) indicate the extent of erosion since the
    withdrawal of the Pleistocene glaciers.]

    [Illustration: Although moving water is an agent of erosion--the
    primary destructive force of mountain masses--it also permits life.
    Even small watercourses, such as this freshet, abound with plant and
    invertebrate life.]

    [Illustration: Going-to-the-Sun Mountain, towering above the St.
    Mary Valley, from the trail to Siyeh Pass. The coniferous forest at
    its base and the alpine tundra plants at its summit are closely
    juxtaposed in space; but if these two communities grew at the same
    elevation they would be separated by thousands of kilometers. Hiking
    from St. Mary Lake up to Siyeh Pass is going, in effect, from
    Montana to the Arctic Circle; but here the life zones are compressed
    and sharply divided rather than extended and overlapping.]

    [Illustration: Setting moon and snow shelf near the summit of
    Heavens Peak. Note stratification of Precambrian sediments.]

    [Illustration: Western redcedars line the shores of Lake McDonald.
    Because of prevailing air currents from the Pacific coast, winters
    in the protected western valleys are moist and comparatively mild,
    and this deep body of water freezes over an average of only one
    winter in four.]

    [Illustration: Moose often follow the spring snowmelt upwards to the
    headwaters of drainages. This bull will remain at Thunderbird Pond,
    at the base of Brown Pass, until autumn, when it will return to its
    Waterton Valley wintering ground.]

    [Illustration: Because of the high reproductive capacity of insects
    and small mammals, if all their offspring survived the earth's plant
    life would be consumed within one year. This is prevented by natural
    controls such as predation and parasitism. The American kestrel
    ("sparrow hawk") feeds primarily on large insects and on small
    rodents such as the meadow vole here.]

    [Illustration: Gray jays are found in the deep coniferous forests of
    the park. In some parks gray jays, or "camp robbers," loiter about
    campgrounds and picnic areas begging or stealing food. In Glacier,
    however, they are seldom noticed as they search out seeds, berries,
    and insects.]

    [Illustration: A generalized predator, the coyote will eat almost
    anything, from berries to carrion. When man eliminated most of the
    coyote's enemies and competitors, including the wolf, grizzly, and
    cougar, it enlarged its range to fill the void. Intelligent and
    social, the coyote thrives despite man's persecution. Although most
    numerous in the prairie community, it ranges up to timberline.]

    [Illustration: The spruce grouse is a year-round resident of the
    spruce/fir and lodgepole communities. It forages on the ground for
    seeds and insects, in winter turning to needles. Several other
    species of grouse occupy different habitats in Glacier.]

    [Illustration: Chipmunks are found in every community, from prairie
    to tundra, in Glacier. Each of the park's three very similar species
    has its preferred habitat. The diurnal counterpart to nocturnally
    active mice, which have the same diet of seeds, berries and
    occasional insects, chipmunks adapt easily to the presence of people
    and become nuisances if encouraged by handouts. Feeding rodents is
    dangerous and is harmful to them. By altering their diets and
    blunting their cautious instincts, daily exposure to "free lunches"
    makes the animals less fit to face the harsh realities of their
    natural environment.]

    [Illustration: Unlike whitetail deer, which remain in lowland areas
    all year, mule deer range upward into high meadows during the
    summer. The bucks, especially, are wanderers and travel together.
    Velvet antlers, worn during the time of summer sociability, presage
    the autumn contests to come.]

    [Illustration: The checkerspot butterfly belongs to the most diverse
    group of animals on the planet--the insects, whose importance can
    hardly be overestimated. They not only help recycle nutrients in the
    living community and provide an abundant food base for other
    lifeforms, but are instrumental in pollinating most of the earth's
    terrestrial plants.]

    [Illustration: Alpine vegetation must be able to survive freezing
    temperature during the growing season, since winter conditions are
    possible even in summer. Early bloomers, such as the glacier lily,
    endure repeated snowfalls during the unstable weather conditions of
    June.]

    [Illustration: Unlike mountain goats, these bighorn rams will desert
    the alpine zone at the approach of winter; they will join other
    bighorns congregating in the lower valleys.]

    [Illustration: In November bighorn sheep rams end their summer-long
    isolation from the ewes, move down from the higher slopes, and begin
    a bloodless but taxing ritual of strength and endurance to determine
    the harem master. The sharp reports of clashing horns may carry for
    kilometers, and the contests continue for weeks until the dominant
    ram emerges. (Note the Many Glacier hotel complex in the valley
    below.)]

    [Illustration: Hummingbirds, like shrews and other small-bodied,
    warm-blooded animals, exist at the theoretical thresh-hold of life.
    Because of their small size, body volume is not large enough in
    relation to surface area to prevent a rapid loss of body heat. To
    compensate for this, metabolic rates must be high; food is rapidly
    processed and used up. Thus, since fat reserves are not practical on
    such small animals, they must eat at frequent intervals.

    Two species of hummingbirds--the rufous and the calliope--are found
    in Glacier. Pictured is a female rufous (which weighs about the same
    as a dime) landing on its lichen decorated nest to feed its two
    young on a protein-rich mixture of nectar and small insects.]

    [Illustration: The insect-eating yellowthroat prefers moist
    habitats. Unlike many of its treetop-dwelling relatives, this tiny
    (10-11 cm.) warbler is usually seen near or on the ground.]

    [Illustration: Bands of bighorn ewes and lambs do not summer as high
    as the rams and are often encountered in the scrub-forest zone. Note
    the gnarled limber pine in the foreground of this photograph taken
    on the south face of Altyn Peak.]

Reaching the mountain wall, the goats scramble upward to a ledge,
sending scree streams pouring from several clefts. Encountering a
narrow, steep snowbank, they do not hesitate but continue across the
slope. Above the rock fingers of this peak the gathering clouds grow
black. A sudden crack of thunder hurries me down the trail.

Although geologically young, the Rocky Mountains in Glacier are composed
of soft sedimentary rocks that are easily assailed by the many agents of
weathering and erosion. If not rejuvenated by continual uplift, these
magnificent peaks will glimmer but briefly in the long memory of the
planet.

Already the sharp countenance of this land is being softened by the
ongoing forces of erosion. Chief among these is water, which attacks the
mountains everywhere. In addition, frost action continually exploits
rock fractures, breaking down blocks of rock into talus and scree.
Avalanche and rockfall sweep down the slopes. Layers of softer rock
erode quickly, undercutting more resistant rock and creating overhangs
which gravity, in time, will collapse.

The lashing rain catches me on this sun-and-storm-contested pass. Ice,
gravity, wind, and especially water--all attack a land that dares the
clouds.

The Rising of the Sun and the Running of the Deer: A Glacier Year

As if to make up for the days-long darkness of this last blizzard, the
peaks today wear snow plumes--long, graceful trails of white, curving up
into an ice-blue sky. Yesterday the snow-mad wind raced through the
forest. Today the motionless trees are cloaked in heavy, glistening
robes, the leafless aspen and young larch bent down.

Moderate snowfall helps many plants and animals survive the winter. For
ground dwellers it provides insulation from the wildly fluctuating
winter temperatures encountered east of the Divide, protecting the
hibernators and providing cover for the many small mammals that remain
active during the winter. Wind-swept ground freezes deep; but under a
mantle of snow life-sustaining heat is trapped, permitting many animals
to survive and allowing the work of decomposers to continue.

But this has been a winter of too much snow and too many temperature
extremes. The heavy snowpack has forced the sharp-hoofed deer to yard up
in great numbers; unable to range freely in deep snow, they are forced
into smaller and smaller confines where their numbers allow them to
break and maintain trails. But in time they exhaust the food supply.
Younger deer, unable to reach the increasingly higher browse line,
starve first. Then the does, heavy with unborn fawns, grow weak and fall
to predators. So the imprisoned herds dwindle quickly this year,
sometimes less than a kilometer from plentiful browse.

Deep snow is also death for many seed-eating birds. As they are unable
to scratch for food, their body furnaces quickly fail, and during a
night of cold wind their fluffed corpses drop into the snow.

Exposed to the noon sun, the snow surface thaws; when refrozen, it is
restructured to crystalline ice. If snow repeatedly thaws and freezes,
an ice barrier is formed, shutting off vital air exchange. Plants are
then subject to rot, and micro-animal life is smothered. Travel beneath
the snow is made more difficult for mice and shrews and they are
deprived of food and cover. Under such conditions their numbers rapidly
decline.

But while many starve in a winter of deep snow, others benefit. The
exposed traffic of small mammals is to the owl's advantage. Foxes and
coyotes more easily run down rabbits and hares on crusted snow. Deer
and, to a lesser extent, wapiti and moose--their hoofs punching through
the snowpack--swiftly tire in deep snow and become helpless before
cougar or wolf, whose lighter weight is supported by the crust.

Grim as this winter's toll becomes, enough will survive to begin the
process of renewal in spring. Last winter, a season of light snow, was a
time of hardship for predators. The deer remained strong, the wapiti
remote on high, windswept ridges, and the small mammals hidden.

Only the water ouzel, winter after winter, seems not to notice the
hardships of the season. Lord of his small world of open water, he sings
in February, wading and swimming his diminished stream to find a
never-failing supply of water insects and small fish. It is a voice of
spring--glad, wild, continual as the moving water--an incongruous song
in this winter-shrouded land.

But with the growing stature of the sun, the grip of winter softens. The
firs and spruce send their loads of snow sliding to the ground. Streams
begin to sing again and soon the lakes increase, the booming of
splitting ice breaking the silence of the valleys. Avalanches thunder
down the steeper slopes, carrying trees to the swollen streams. Rivers
hiss and rage, speeding the debris along. A spring that comes too
suddenly will bring flood to lower elevations.

Snow geese thread through the valleys, and ground squirrels tunnel up
through snow to find invasions of birds returning from the south. Soon
the three-petaled wakerobins appear, chasing the snowline up the ridges.
Glacier lilies and Calypso orchids are next, and with the shooting stars
spring arrives.

The melting snow releases a new group of animals to populate the
winter-thinned land. Up come chipmunks. Bears reappear. Young red
squirrels, helpless and blind, squirm in their nest holes. Hidden dens
rustle with pups and kits. Soon warm days will bring them out and the
business of learning to cope with their world will begin.

All life responds irresistibly to the growing strength of the Sun.
Cottonwood, willow, and maple come into flower and unfold new leaves;
green needle clusters spot the limbs of larches that in winter had
seemed lifeless snags among the other conifers. Beneath the soil of
prairie, meadow, and forest, in the mud of lakes and ponds, other life
stirs; armies of insects, spiders, crustaceans, amphibians, and fish
will strive to complete their life cycles against the formidable odds of
a predatory world.

Spring reaches higher up the mountains, the lowlands passing into
summer. Wapiti and mountain sheep follow the rising tide of succulent
browse up to the high meadows. In forest, grove, and meadow and along
the stream new fledglings appear--thrush, vireo, hummingbird, waxwing,
harlequin duck, bluebird, osprey, and flicker--as holes, nests, and
cavities brim with begging mouths.

In the alpine meadows, where snow overlaps the spring and winter follows
hard behind the summer, the growing season is short and the climate
unstable. Sensing the stronger light, flowers push up impatiently
through the snow and hasten into bloom. Pikas and marmots scurry and
sunbathe among the rocks of scree slopes.

Summer matures in ripening huckleberries, and the bears that grazed the
spring grasses now gorge themselves fat. Dry days of August bring
probing lightning, threatening the forests with fire.

Sweeps of beargrass reach their climax now in the highest meadows. In
dizzy succession wildflowers set seed. Fat and sluggish, marmots and
ground squirrels disappear beneath the rocks. The golden eagle must
search longer each day to find prey within its vast domain.

Autumn lingers in the valleys and on the flanks of low ridges. The
morning sun glints on hoarfrost, firing the yellow leaves of larch,
aspen, birch, maple, and cottonwood, and shines on the blood-red berries
of mountain-ash. Soon a night of killing frost will bring down the
corpses of insects and spiders by the millions. The reptiles and
amphibians, being cold-blooded animals, seem out of place in this
long-wintered land. Unable to maintain body temperatures appreciably
above their surroundings, they are the first to seek the protection of
hibernation, collecting in dens or burying themselves beneath the ooze
of pond bottoms.

Songbirds gather and leave the valleys. The harsh cries of jays sound
ominous now in the forest. Only the chickadees seem to ignore the long
tree shadows; their ceaseless conversations carry through the leafless
underbrush as they busily search for seed.

Velvet has gone to bone, and in these final noon-warm days the rut runs
through the land. It begins in the valleys in September with the
joustings of deer and moose and the buglings of bull wapiti puncturing
the forest silence. By November the higher meadows ring with the
collisions of bighorn rams who compete for ewes by smashing together
their massive, curled horns. On high slopes mountain goat billies
posture and swagger; head to tail, they circle, threatening each other
with dagger-like horns.

From Flathead Lake, 100 stream kilometers to the south, kokanee salmon
return to spawn in the clear, cold shallows of McDonald Creek. Gathering
bald eagles surround the stream, again and again lifting vulnerable fish
from pool and riffle. Perched by the hundreds along the stream course,
their white heads and tails glistening against the dark trees, they
stand out like lanterns strung for a banquet.

Now the stinging wind comes down from the peaks and shuts the lakes.
Life slows or sleeps. Ptarmigan, snowshoe hare, and longtail weasel, all
wearing winter white, seek shelter and food in a silent land where
spring and yellow lilies seem forever lost.

[_]
All life faces one ultimate challenge: to survive or not, to reproduce
or fail, to bring one's kind to tomorrow's sun or vanish forever. This
land is harsh. To survive in nature demands skill in the individual,
excellence in the species, and a chance from the environment.

    [Illustration: The mink, a solitary predator associated with
    low-elevation watercourses, preys on anything it can catch and
    subdue.]

                      Plant-and-Animal Communities

Over Going-to-the-Sun Road

I like to begin with St. Mary, a lake the whitecaps love to run. From
the far passes the several winds gather and collect, arranging long
lines of white waves for the race downlake. Past the purple scree of
Mahtotopa and Little Chief they go, white as the headdress of
Going-to-the-Sun Mountain, colliding, collapsing along the promontory
snares about the Narrows. Onward they press, spreading out and setting
sail for the straight rush to the final shore where a line of
cottonwoods sings with a sound like applause.

Across the lake the timbered ridge starkly contrasts the finger of
prairie that claims the north shore. This is a flower-glad place, a
meeting-ground for mountain and prairie plants. Along the road the
grassland holds the conifers back, allowing only scattered clumps of
aspens.

Finally, at Rising Sun, beneath the shadow of Goat Mountain, the prairie
ends and wind-seasoned Douglas-firs announce the coming forest.

There's excitement now, with the prairie heat gone, the wind scent raw
with fir and high meadows, honed by waterfall and tall, dank rock. Our
mountain thirst is never extinguished, and a road that tightens down to
cliff face and sudden turn brings back to our blood the ancient need to
go to the highest place.

There is sword-edged Citadel, and the snow-flanked spike of Fusillade
holding court like a queen in this valley of peaks; then the dome of
Jackson and the Gunsight notch. Our eyes are kept high, transfixed at
last by looming Heavy Runner and the distant promise of Reynolds.

Looking for mountain goats, we scan the walls around the sweep of Siyeh
Bend, catching a glimpse of the trail that crosses the scree to hidden
Piegan Pass.

Beargrass heads lean out above the road like old men conferring on the
view. The purple trumpets of penstemon crowd the rocks, and spots of
Indian paintbrush lead like a blood-trail to the higher slopes.

Intoxicated now, feeling the fresh full force of the wind from Logan
Pass, we race on. We hardly notice the struggle of the forest in
Reynolds Creek far below, how it thins and loses strength in its own
hard climb. We sweep past it on the broad magnificence of this pass.

Level but a moment, the road dips to a shelf on the headwall above Logan
Creek and swings over the great sculptured cliff of the Garden Wall. For
several kilometers this masterpiece of a road glides down a constant
grade, squeezed between rock face and space, twisting into tight
drainages--a road for storm lovers, wet with spray and snow-seep, its
quick turns concealing sudden winds.

Mighty, snow-robed Heaven's Peak appears, taking our attention from the
Pass-group mountains and the hanging valley that spills Birdwoman Falls.
Northward is the great array of peaks encircling distant Flattop,
jumbles of mountains and glaciers. How are we to notice the forest far
below?

Not until we have passed the Loop and are moving past the blackened
snags of a recent burn do we realize the stature of this forest. The
long road down will take us into a valley much deeper than any on the
eastern side. Near Avalanche Creek are trees we have seen nowhere else
in the park--giant western redcedars, western hemlocks with their
nodding tops, monstrous black cottonwoods with bark so deeply furrowed
that it looks hewn by hatchet.

We take a long ride down the valley, past the low pyramid of Mt.
Stanton, final peak in the Livingston Range. Near the outlet end of Lake
McDonald, birch and aspen again appear in numbers, and the road enters a
crowded stand of lodgepole pine.

Our memories cluttered with mountains, waterfalls, and snowfields, we do
not quite realize the significance of this 80-kilometer journey. We have
crossed the boundaries of several different plant-and-animal
communities, spanning a range of climate that would be encountered on a
5,000-kilometer north-south journey at sea level.

At first glance the various trees, wildflowers, and animals seem
randomly distributed, scattered about like the distant mountains. But
mountainous terrain represents an organized high-rise approach to life.
From the lowest, most protected valley to the highest wind-and-ice-cut
summit, the life-forms align themselves, each according to its own
climatic tolerance.

Here too can be seen the great cycles of nature: fire and regrowth, the
building of soil and its erosion, the incessant duel of the eaters and
the eaten.

In the following sections we will spend some time in these various
communities, from prairie to tundra.

Groves and Grasslands: The Prairie Sea

There is something about spring on the prairie that gets me up before
dawn. I like to watch the seasons change their guard over the landscape,
from the wintry cold of pre-dawn dark to the spring-scented morning air
to the hot summer-foretaste of the noon May sun.

Hoarfrost surrounds these patches of pasqueflowers, blue goblets on
downy stems. On this windless night, frost has formed everywhere,
reclaiming for a time its vast winter range, sparkling over the green
handiworks of spring.

But the god of the growing grasslands is the sun, and it now proclaims
itself, stretching out to make the mountains shine. With its assault the
frost collapses, becoming bright beads on grass tip and leaf joint by
which a beetle might refresh itself.

Spring is best perceived ant-level, at its ground beginnings, where the
bright yellow-green tips of new grass shoots reclaim the winter-blighted
land. I look closely at a drag line of spider silk; a necklace of
dewdrops slides down, collects to a moment's greatness, in which I
briefly see a curved horizon, the morning sunburst, and myself, before
it falls away.

Getting up from my prone position, my belly damp from the prairie earth,
I startle a whitetail jackrabbit; bounding high, it zigzags off. The
commotion disturbs a distant badger, which faces about from its diggings
to confront danger in whatever form it might take. It swings its snout
to scent the air. Somewhat uncertainly, it returns to the business of
hunting, then hesitates, swings about once more and waits, myopic,
patient.

Satisfied at last, the spurt of the now distant rabbit lost in its
brain, the creature snorts a defiance at the mystery and resumes its
morning gopher hunt.

Overhead a marsh hawk skims past, its flight erratic as a butterfly's.
Far away a magpie rattles at the passing hawk and takes flight, briefly
flashing black and white.

[_]
It is easy to see only pieces in the natural puzzle--a badger throwing
dirt, horned larks dipping into wind, black ants dragging the rosette of
a dead spider--and be satisfied with the scattered scenes. But at last,
to make it meaningful, we must complete the picture. There is that
special joy in discovering larger schemes: green plants utilizing
sunlight; a rabbit building its days at the plants' expense; the falcon
tearing the rabbit meat for its young; magpies picking at the fallen
falcon; and then, in the end, all returning to the earth.

Here on the prairie, as in every plant-and-animal association, the
ancient drama repeats itself over and over; the distant tundra is a
drastically different stage with different actors, but the cycle is the
same. Life depends upon the interaction of all its many forms. Unseen
bacteria are as necessary to the land as green grass; the meadow vole
and the coyote are as much a part of the prairie as the grasses.

The secret of life rests in the wonder of photosynthesis. Only green
plants can manufacture food from the earth's raw minerals. This is the
vital first step upon which the great pyramid of animal and plant life
is built. Using energy from the sun, green plants combine water and
carbon dioxide to synthesize sugar, and give off oxygen as a by-product.
The caterpillar takes its energy from the plant tissue, converting to
protein the sugar and minerals in its body. The caterpillar is then food
for a spider or other predator. A yellow warbler may take the spider and
in turn be ambushed by the prairie falcon. Thus the energy produced by
the plant travels through the food chain. When the prairie falcon dies,
scavengers--including insects and other invertebrates, birds, and
mammals--redistribute its wealth among themselves; the rest is
decomposed by bacteria. Thus, eventually, the nutrients on which the
plants depend return to the soil.

When we look at any living organism, whether it is plant, herbivore,
carnivore, parasite, scavenger, or decomposer, we are soon made aware of
its associations with other living things, each puzzle piece leading us
to another and another. We begin to see a picture whole--the fox, meadow
mouse, grasshopper, bunchgrass, and sparrow hawk--all interlocked.

Geologically speaking, grasslands are a recent development. As the Rocky
Mountains were being uplifted, the prevailing warm, moist climate began
to change. The rising mountain mass intercepted moisture-laden winds
that blew in from the Pacific, creating a rain shadow that lengthened
eastward as the mountains rose higher. A continental climate,
characterized by severe winters and dry, wildfire summers gradually took
shape, extinguishing the great forests that had grown across the
continent's interior. Herbaceous plants, which had been evolving amid
the forests, inherited the land.

Unlike trees, grasses die back to the ground each winter, hoarding their
life-germ beneath the protecting soil. Growing not from the tip but from
the joints, grasses regenerate quickly after fire or grazing. Suspension
of the normal metabolic processes enable the grasses to go dormant and
thus survive periods of severe heat and drought.

Although the great prairie sea washes up against Glacier's eastern
boundary, with estuaries probing into the mountain valleys on the drier,
south-facing slopes, the grassland community comprises less than 5
percent of the land area of Glacier National Park. This includes the
puddles of prairie west of the Divide that interrupt the dense
coniferous forests along the North Fork of the Flathead River.

From the pasqueflowers that bloom in early May to the asters and
goldenrod of September, these summer-long gardens of grasses and flowers
lean with the wind. Here are timothy, oatgrass and the
bunchgrasses--rough fescue, bluebunch fescue, and bluebunch wheatgrass.
Among the grasses bloom bitterroot, blue camas, lupine, gaillardia,
balsamroot, cinquefoil, sticky geranium, and wild rose.

                                                     _continued on p. 68_

    [Illustration: The Forests of Glacier

    From the lush redcedar-hemlock forest in the McDonald Valley to the
    subalpine fir, whitebark pine, and Engelmann spruce struggling for
    existence near treeline, the forests of Glacier reflect the
    conditions of temperature, exposure, soil, and drainage prevailing;
    and each forest has its characteristic association of understory
    trees and shrubs, herbaceous ground cover, and vertebrate and
    invertebrate animal life.]

    [Illustration: Life Zones

    Many physical and climatic factors determine the range of Glacier's
    plant-and-animal communities. Boundaries between communities are
    seldom sharply defined, but rather merge together in broad zones of
    transition.

    With elevation gain, average daily temperature drops at the rate of
    5° per 900 meters. Precipitation, wind velocity, and evaporation
    loss increase. Soil thins. These factors, along with others such as
    fire frequency, north or south exposure, and availability of
    moisture, combine to determine the range of each community.

    In the forest community below 1,800 meters, Douglas-fir, lodgepole
    pine, and western larch predominate. In the valleys, Engelmann
    spruce and subalpine fir are found. The somewhat lower and much
    better watered western valleys of the park support western redcedar
    and western hemlock.

    Treeline is the upper limit to which the tolerances of trees to
    environmental conditions permit them to grow. Because there are so
    many controlling factors (wind, temperature, exposure to sunlight,
    snow cover, etc.) treeline in the diagram is only approximate. In
    Glacier it averages 2,000 meters. Avalanche chutes or sheer cliff
    walls may suppress it to below 1,500 meters; on protected slopes it
    may be as high as 2,150 meters.

    At the eastern edge of the park below 1,200 meters, the forest gives
    way to the prairie community, composed mostly of soft-stemmed plants
    adapted to the conditions of low precipitation that prevail here in
    the rainshadow of the mountain range. Clumps of aspen, found in the
    prairie in sheltered spots, occur here in the transition zone
    between prairie and forest.]

    [Illustration: A Mountain Profile

    This diagram represents the eastward-facing slope of a hypothetical
    mountain near the eastern boundary of Glacier National Park. Its
    life communities are somewhat different from those of mountain
    slopes at the western edge, chiefly because of the differential in
    annual precipitation.

    Illustration: Here, above approximately 2,750 meters, in a realm of
    ice, snow, and barren rock, there is little life.

    Alpine tundra

    Below 2,750 meters and above 2,000 meters, depending on other
    factors such as exposure to sun and wind and steepness of terrain,
    exists the alpine tundra community, with vegetation similar to that
    of the vast, essentially level, treeless zones of the Arctic.

    Scrub-forest

    Roughly between 1,800 and 2,000 meters, the dominant vegetation is
    scrub-forest. Trees here are stunted; except in sheltered spots they
    are more or less prone rather than upright. Net growth is slow, not
    only because of the short growing season but also because of the
    pruning effect of icy mountain winds. Very few tree species can
    survive in this harsh habitat.

    Coniferous forest

    In the forest community below 1,800 meters, Douglas fir, lodgepole
    pine, and western larch predominate. In the valleys, Engelmann
    spruce and subalpine fir are found. The somewhat lower and much
    better watered western valleys of the park support western redcedar
    and western hemlock. See page 54

    Prairie

    At the eastern edge of the park below 1,200 meters, the forest gives
    way to the prairie community, composed mostly of soft-stemmed plants
    adapted to the conditions of low precipitation that prevail here in
    the rainshadow of the mountain range. Clumps of aspen, found in the
    prairie in sheltered spots, occur here in the transition zone
    between prairie and forest.]

    [Illustration: The Forest Community

    A forest is organized vertically like an apartment house or office
    building, with layers corresponding to stories. The _canopy_ is the
    branches and foliage of tall trees that form a roof over the
    community. Below the canopy are the _understory_ trees: young
    individuals of the canopy species; and small, shade-tolerant trees
    that will never become part of the canopy. Beneath the understory
    branches is the _shrub layer_, occupied by knee-high-to-man-high
    woody plants; beneath that is the _herb layer_, where most of the
    ferns, wildflowers, grasses, and smaller woody plants grow. The
    _forest floor_ is the zone of mosses, mushrooms, creeping plants,
    and forest litter (leaves, twigs, needles, feathers, bits of bark,
    animal droppings, etc.). The forest has a "basement," too,
    interlaced by plant roots, mycelia of fungi, and tunnels of myriad
    animals.

    Each layer of the forest has its characteristic animal species, but
    most forage over more than one level. Some nest in one story and
    feed in another. The red squirrel races back and forth from the
    forest floor to the highest branches.

    The forest community also has a socio-economic organization. Every
    animal (and plant) takes up space and consumes a portion of the
    available nutrients. Each has a place in the community food
    chain--as, for example, _herbivore_, _carnivore_, or _scavenger_.
    Each directly or indirectly affects all the other organisms.

    The Forest Community

    The role of a species in the community, like the job and social
    function of a person, is its _niche_. Similar species of animals
    have different niches, thus lessening competition for food and
    living space. Thrushes hunt close to the ground; vireos and kinglets
    hunt among the branches; flycatchers snap up airborne insects. The
    flicker feeds upon insects, excavates nesting holes that are later
    occupied by other species such as squirrels and owls, and is preyed
    upon by the great horned owl; its niche is _insect exterminator /
    food for carnivores / homebuilder_. The great horned owl, hunting
    mammals, birds, and reptiles by night, preys on species different
    from those hunted by the goshawk, and thus occupies a parallel
    niche. When it dies, its remains, like those of other animals, are
    decomposed and return to the soil.]

  Canopy
    Great Horned Owl
    Yellow-bellied Sapsucker
  Understory
    Flying Squirrel
  Shrub Layer
    Ruffed Grouse
  Herb Layer
    Red Squirrel
    Western Toad
  Forest Floor
    Shorttail Weasel
    Scavenging Insects
    Deer Mouse
    Garter Snake
  Soil Layer
    Ground Squirrel
    Earthworm
    Masked Shrew

    [Illustration: Sun, Green Plants, and Animals

    The sun is the source of energy for any plant-and-animal community.
    Green plants draw nitrogen and minerals from the soil, and in a
    process called photosynthesis use sunlight to convert raw materials
    (carbon dioxide and water) into carbohydrates (sugar, starch,
    cellulose), giving off oxygen as a by-product. Besides burning
    oxygen, animals depend on plants for food.

    Green Plants, trees and shrubs, grasses and sedges, wildflowers,
    ferns, mosses, algae and lichens--are fed upon by animals, which are
    unable to manufacture their own food.

    The Redback Vole, like other rodents, pikas and hares, seed-eating
    birds, grazing and browsing hoofed animals, and herbivorous insects,
    derives its energy from the seeds and other parts of green plants
    that it eats.

    The Garter Snake, feeding upon the vole, is dependent upon plants
    even though it does not eat them.

    The Great Horned Owl, preying upon the garter snake, is one more
    step removed from the green plants--but still dependent on them.

    Scavengers such as carrion beetles feed upon the carcass of the owl;
    the remains are then attacked by Decomposers, primarily bacteria,
    that break down the animal tissues into basic organic compounds.

    The Soil, enriched by the minerals and carbon and nitrogen compounds
    added to it by the decomposers (and by other processes such as fire)
    supports new green plant growth.

    Thus energy derived from the sun flows through the ecosystem in a
    food chain. A plant-and-animal community is a complex, interlocking
    web of such food chains.]

  Sun
    Green Plants
    Redback Vole
    Garter Snake
    Great Horned Owl
    Scavengers, Decomposers
    Soil

    [Illustration: A Pyramid of Numbers

    Necessarily, the number of plants in an ecosystem far exceeds the
    number of plant eaters, and the number of prey species must exceed
    the number of predators. During its lifetime, a golden eagle will
    consume a vast number of lesser animals. The combined mass of prey
    animals necessary to sustain an eagle greatly outweighs the eagle
    itself. Ecologists refer to this proportional relationship of mass
    between each link in the food chain as the _pyramid of numbers_.

    The diagram represents a numbers pyramid for the alpine zone.
    Because of its limiting environment, the alpine zone supports a
    lesser plant mass than the forest zone. As a result, the carrying
    capacity of the alpine is less than that of the forest.

    1 Kilo

    _Tertiary_ (third-order) _consumers_ are the predators (Golden
    Eagle, Swainson's Hawk, etc.) that feed upon other predators.
    Because of the 90% loss of energy at each level of the food chain,
    there will be very few hawks and eagles in comparison to the numbers
    of marmots.

    10 Kilos

    _Secondary consumers_ are the predators (weasels, shrews,
    carnivorous insects and birds, etc.) that eat herbivores. The
    animals at this level of the pyramid are often--though not
    always--larger than the animals they feed upon. But they are much
    less numerous, because it takes many prey animals to sustain one
    predator.

    100 Kilos

    _Primary consumers_ (plant eaters, or herbivores) convert plant
    tissue into animal flesh. In the process about 90% of the energy
    stored as plant food is lost, mostly as heat energy. In the alpine
    community the herbivores include pikas, marmots, ground squirrels,
    and ptarmigan, as well as herbivorous insects.

    1,000 Kilos

    _Producers_ are the green plants at the base of the food pyramid,
    manufacturing food for the animals of the alpine community. The
    _biomass_ (total weight) of each level of the food chain is ten
    times (more or less) the weight of the stage above it: 1,000 kilos
    of green plants will produce only 100 kilos of primary consumers.]

    [Illustration: Great horned owls are the nocturnal equivalent of
    Cooper's hawks and goshawks in the low-elevation forests of the
    park. Large and powerful, they are capable of taking prey as big as
    skunks. This young bird, disturbed on its day roost, clacked its
    bill and fluffed its feathers in a menacing manner.]

    [Illustration: The only sizable mature stand of ponderosa pine found
    within the park is along the North Fork truck trail. A scattering of
    old ponderosas growing at the lower end of Lake McDonald suggests
    that at one time ponderosa forests were more extensive in this
    region than at present.]

    [Illustration: A black bear near treelimit. Bears will eat almost
    anything, from ants to carrion, grass to garbage. Color phases
    include brown and blonde bears. Unlike the larger, more aggressive
    grizzly, which ranges out onto the plains, black bears are strictly
    forest creatures.]

    [Illustration: The water ouzel, or dipper, a creature of fast
    mountain water, is admirably outfitted to cope with its demanding
    environment. Stubby wings, chunky body, short tail, and oily plumage
    allow it to walk under water, where it scavenges for aquatic insect
    larvae and small fish. In flying up- and down-stream, ouzels never
    shortcut but follow the winding streamcourse.

    As long as there is open water, the dipper suffers no hardship from
    the mountain winter. Then, when the land is shut down and lakes are
    frozen over, this little bird carries on in its mountain-stream
    habitat, plunging into the cold water to find food, and pausing
    occasionally to sing.]

    [Illustration: Ouzels construct their nests of living moss on cliff
    faces or ledges where constant spray keeps the moss moist. At
    fledging, the four young of this nest in Avalanche Gorge tumbled one
    by one into the torrent below, to be collected by the adults in
    quieter water downstream. Within a day they appeared to have
    mastered the underwater gymnastics and were feeding on their own.]

    [Illustration: From their lowland wintering grounds, wapiti move up
    to higher elevations in spring. Summer range in the park is
    abundant, but winter range is limited; as a result, wapiti have a
    tendency to increase their populations beyond the carrying capacity
    of available winter range. In a severe winter many starve. But in a
    balanced ecosystem such loss is not waste, for the carrion helps
    sustain scavengers; it is an important initial food source for bears
    emerging from hibernation.]

    [Illustration: Cedar waxwings nest in moist areas of low valleys
    where fruits and berries are abundant. Although they also subsist on
    insects (which they can capture on the wing), their weakness for
    fruit is so pronounced that the birds will sometimes gorge
    themselves until rendered incapable of flight.]

    [Illustration: The Columbian ground squirrel is found at all park
    elevations, from prairie to alpine meadow. Hibernation occupies
    almost three-quarters of its five-year lifespan. Unlike other park
    ground squirrels, it lives in colonies. Although not as tightly
    structured as a prairie dog town, the association is beneficial to
    all members in that danger is readily detected.]

    [Illustration: The tundra community is encountered above Preston
    Park on the Siyeh Pass trail. Mt. Reynolds, a classic example of a
    horn, dominates the distant Logan Pass area.]

    [Illustration: Camas blooms in the prairie community along the Red
    Eagle road. An important staple, camas bulbs were gathered as food
    by Indians.]

Conspicuous also are many insects--including grasshoppers; flies; ants,
wasps and bees; butterflies and moths; bugs; and beetles--which fulfill
important roles as herbivores, carnivores, and scavengers while also
acting as pollinators for flowering plants and providing an abundant
food source for other animals.

Below the ground are the tunnels. Burrowing is an important means of
survival on the open prairie, and life underground is extensive. Some of
the animals are rarely seen--the northern pocket gopher, for example,
with a diet of underground insects, grubs, worms, and roots, spends most
of its life tunneling just below the surface. Others, like the badger,
leave their burrows during the day to dig for rodents. Most conspicuous
of the burrowing animals in the park's grasslands is the Columbian
ground squirrel. Its alert upright stance has earned it the nickname
"picket pin." When danger approaches from the air or on land, its shrill
alarm whistle passes the warning to others of its kind.

Where prairie and forest meet, a never-ending struggle for dominion is
waged. The isolated patches of prairie that dot the North Fork Valley
near Polebridge hold the great forest of the park's northwest region at
bay.

This broad valley, floored with coarse glacial outwash and terraced
downward to the deep channel of the North Fork River, presents a graphic
battleground between grass and tree. Lining the upper terraces, from
which they glower down on the dry, well drained grass flats like a line
of warriors, are the Douglas-fir, western larch, and ponderosa pine.
Seedling trees continually invade the prairie. But most perish early,
their shallow roots no match for the extensive root systems of the
fast-growing, moisture-greedy grasses. If encouraged by a series of wet
summers, however, the young lodgepoles quickly gain stature. They had
made significant inroads at Big Prairie when the disastrously dry summer
of 1967 killed most of these 15-year-old pioneer trees.

These North Fork grasslands and the immediately surrounding lodgepole
pine forests are an important spring range. Deer, wapiti, and
grizzly--and, in the wetter areas, moose--graze or browse here. And
here, low on the western slopes of the Livingston Range, are the park's
only stands of ponderosa pine, a tree that prefers warm, dry habitats.
As a result, at low elevations it often merges with the prairie
community.

Groves of aspen colonize the eastern prairies in areas where there is
sufficient water and protection from wind. These aspen parklands are
important havens for animals. Wherever two differing communities
interact, a phenomenon known as "edge effect" occurs. Here wildlife
exists in abundance; the animals that favor forest cover mingle freely
with those that prefer open areas. Aspen groves--supporting grasses,
herbs, and shrubs beneath their thin canopies--are favored haunts for
grouse, varying hare, deer, and wapiti, all of which find among the
trees abundant food, shelter and concealment. Populations of insects,
small mammals, and birds, which are high for the same reasons, attract a
wide range of predators.

Isolated aspen groves are characteristically dome-shaped. Because aspens
are capable of reproducing themselves vegetatively, the grove slowly
expands outward from the parent tree. As a result, most of these groves
are either exclusively male or exclusively female.

Since quick-growing aspens provide a bountiful food source for beaver,
streams near these trees are often dammed by the rodents flooding
lowlands and creating additional habitat in the form of willow flats.
Another "edge effect" is established, attracting animals found near
water. Waterfowl, marsh birds, moose, mink, muskrat, skunks, amphibians,
and many others find such areas to their liking.

[_]
Before the appearance of the white man, these eastern prairies were a
paradise for animals. Once, on the summit of Rising Wolf, light-headed
from the climb and the view of endless prairie, I fancied that I saw
that vast, undisturbed animal panorama spread before me.

Principally there were the bison, darkening the uneven land. Pronghorn
bands flashed white on ridgetops, and moose moved through the long
fingers of willow that extended eastward with the rivers. Caribou and
wolves inhabited the shadows. Among vast cities of prairie dogs, swift
fox and grizzly roamed. There were the clamorings of sandhill crane, and
white clouds of trumpeter swans.

This land, endowed with a wealth of wild grass, wore its wilderness
well.

The Forest

On Gunsight Pass, the rain lancing down, I found a sharpedged rock that
split the continent in two. On both sides the rain rivulets ran down, a
fraction of an inch determining the stream's destination: Pacific or
Atlantic.

The Continental Divide is a mighty barrier, a line of consequence that
does more than determine watersheds. Its effect in Glacier is dramatic,
as a look at the forests will reveal.

Obstructing the eastward flow of the moisture-laden Pacific winds, the
Divide extracts a heavy annual tribute of precipitation from the air
mass, forcing it to rise up the mountain chain, where it cools and
condenses. Chief benefactors are the low western valleys, which respond
with a lush growth of Pacific coastal-type forests.

The eastern valleys, however, deprived of abundant annual moisture and
exposed to the wind and temperature ravages of the prairie's continental
climate, support a dramatically different kind of forest. Here Engelmann
spruce and subalpine fir are the climax trees, contrasted with such
trees as the western redcedar and western hemlock of the mild and moist
McDonald valley.

Elevation exerts an additional restriction on the distribution of tree
species. Since climatic conditions vary with change in elevation--lower
temperatures resulting in shorter growing seasons, and increased wind
exposure resulting in greater loss of moisture through evaporation--we
would expect to find the forest composition change as we ascend a
mountain slope. In Glacier, eastern valleys average 240 meters higher
than western, and thus even if they had more moisture they would not
sustain the redcedars and hemlocks. All plants have range limits, some
narrow, some broad; and they excel where their particular set of
preferences as to moisture, soil, sunlight, and wind exposure are best
met. On sites that do not meet their optimum requirements, they face
being crowded out by species better adapted to the prevailing
conditions.

Physical features of the land determine vegetation also. Certain trees
prefer the moist areas along a streambed--the great black cottonwoods,
for example. And on steep hillsides, avalanches prevent the growth of
climax trees, permitting instead only shrubby, pliant
growth--mountain-ash, mountain maple, alder, menziesia.

Forest communities are named for their dominant tree species. Thus, an
area in which Douglas-fir dominates is called a "Douglas-fir forest."
Glacier does have forests in which Douglas-fir is the climax species;
these are chiefly dry areas, below 1,800 meters, with south and west
exposures. But we usually associate the park with its Engelmann
spruce-subalpine fir forests, found extensively between 1,200 and 2,100
meters, and with the western redcedar-western hemlock forests in the
McDonald valley.

Because forests mature slowly and change is usually imperceptible, we
are tempted to think of them as static and eternal. But since a forest
is a community of living things, it responds to changes in the
environment. Subtle physical or climatic changes, such as a rising or
falling water table or a slight increase or decrease in annual
precipitation, will favor some species of trees and hinder others,
eventually altering the composition of the forest.

Other changes are more dramatic. Most notable of these is fire.

                          From Fire to Forest

Heat lightning, glimmering soundless behind the western peaks. Then the
first low rumble. At first the flashing had been from cloud to cloud,
but now, as the storm nears, the first ground-spears appear, lighting up
the night. Here is a big storm, many-celled, engulfing more and more
territory beneath its angry bulk. Lightning dances into the dry August
forest. In their towers the lookouts stay awake.

Close strike and a flare-up! The ridge snag burns like a Roman candle,
sending bright embers down. Valley, ridge, and peak blink on and off
with blue light as the storm roars like night-firing artillery.

Passing overhead, the low cloud belly brings a sudden lash of rain. But
it is not enough: tomorrow will mean long hours of fire watch.

The next day dawns clear, a morning of heavy dew. The ridge strikes did
not ignite the forest. Inspecting the storm path, aircraft and lookouts
find no evidence of fire.

But two days later, in a morning of high wind, thin smoke plumes rise
upward. Smoldering in the thick duff of the forest floor, a lingering
hot spot explodes with the fanning wind. It quickly spreads from a
hectare to ten while the quadrants are called in and the hot-shot crews
dispatched; then to a hundred, bringing in the smoke jumpers and
mobilizing the vast fire-control network. A thousand hectares, perhaps
ten thousand might burn this week of big fires.

In the resulting skeleton forest, the scene of devastation is almost
overpowering: life seems forevermore excluded from this blackened ruin.
But fire is nothing new to forest communities. We may think fire demonic
because it takes from our life span this block of mature forest, a sight
we will never again see in this place. But nature does not operate in
terms of human time scales. This forest is simply pushed back closer to
its starting point, to begin again its long progression toward a climax
vegetation cover.

                           Forest Succession

Through a series of complex vegetation stages, each characterized by
different herbs, trees, and shrubs, the forest slowly returns to the
type of vegetation best suited to the physical and climatic conditions
of the site; this is called a climax community. The fact that most of
Glacier's forests are in some stage of recovery from fire accounts in
part for the mosaic of forest cover found here.

The forest of Huckleberry Mountain on the Camas Creek road was consumed
in the 1967 fire. By 1969, among the charred, lifeless trunks of the
former forest, lush grass and sunloving fireweed, thistle, and
paintbrush were growing. And by 1974 lodgepole pine seedlings along the
road were a meter or two high. Lodgepole is a fast-growing tree that
requires full sun to germinate. Forest fire is necessary for the
regeneration of these trees: the intense heat causes the tightly closed
cones to open, releasing the seeds that will establish the forest. So
young pines developed among fireweed, spiraea, willow, and mountain
maple shrubs.

The lodgepole forest near the western entrance to the park has been
developing since 1929, when fire destroyed the redcedar-hemlock forest
in the area between Apgar and West Glacier. Beneath the scattered spires
of old larch that survived the burn, the lodgepoles have now grown up,
forming a canopy that shades the forest floor. Because lodgepole live
only about 80 years and will not germinate in shade, this forest will
not exist long. Shade-tolerant Douglas-fir, white pine, Engelmann spruce
and western redcedar seedlings are now taking hold. But the physical
characteristics of this area--the climate, terrain, and soil--are
ultimately most favorable for western redcedar and hemlock; and unless
other disruptions intervene, this area will eventually again become a
dense redcedar-hemlock forest.

But this will not happen quickly. The soil after hundreds of years of
collecting debris will again become rich and moist. Young hemlocks will
germinate on and near decaying logs. When old larches, firs, and pines
fall, the slow-growing redcedars and hemlocks will take their places in
the canopy.

Forest succession is a more complicated story than this; it is a
fascinating study involving herbs, shrubs, small and large trees, and
animal populations. From location to location it will vary; only in its
broad outlines is it predictable. It is based on the observation that,
given time, a forest--or any other plant community--will progress until
it reaches climax--that is, the stage that will perpetuate itself.

[_]
How then are we to think about fire? Increasingly, experts are concerned
not so much with fire suppression as with fire management. For
suppression has at least three disadvantages: it allows the accumulation
of unburned fuels that can result in "fire storms" when they are finally
ignited; an undiversified climax forest is more vulnerable to disease
than is a mixed forest; and a dense forest canopy discourages shrub
growth, an important food source for deer, wapiti, moose, and smaller
animals.

As the well-being of the deer herd depends on the predators that thin
its numbers, so the long-term well-being of the forest depends on fire
to rejuvenate it periodically. We must realize that wilderness is
identified with fire, landslide, avalanche, windfall, and flood. Nature
not only has learned to cope with these agents of change--she depends
upon them for maintaining the delicate balances between landscape and
life. There is in the business of nature, after all, more than the
pleasing of man's eye.

                             Spruce Morning

Of all times to get a rock in my boot! I had just started out, the
morning was still cool in this eastern valley, and the heavy pack was
not yet biting into my shoulders. Sitting down beside the trail, I
leaned the pack against the base of an old spruce and began unlacing.

I could hear the scratching of the red squirrel descending to
investigate, but I didn't look up until it let go with long indignant
chatter at finding its territory invaded. I plunked out the pebble and
began relacing my boot. Cautiously the squirrel came down, pausing
frequently to scold, its lower jaw quivering with rage and exposing
yellow rodent teeth. Neighboring squirrels joined in and soon the trees
danced with flicking tails.

Down the squirrel came, almost to the ground, then raced back up the
tree, stopping at each lateral branch to deliver a vocal broadside.
Finding no danger to themselves, the other squirrels soon quit the
uproar and went about their morning business. I was beginning to suspect
that I was committing some graver offense than the mere exercise of
squatters' rights--perhaps I threatened its cache of fir cones. Then
into the corner of my vision shot another form, streaking soundless as a
shadow; the squirrel also saw it--but too late. With a thin terrified
squeak, the rodent started to go higher; but the pine marten was above
it. The squirrel quickly reversed itself, sending bits of bark showering
down.

As the squirrel leaped from the tree in desperation, the marten overtook
it in mid-air; they came down together. Clamping the limp creature
firmly in its jaws, the marten strode up the incline of a fallen spruce.
Before it hopped off onto a shelf of higher ground to disappear, it
looked briefly back at me. I fancied I could read, fixed in its eyes, a
certain recognition of my having distracted its prey.

A breeze made me shiver, snapping me back from that swift vision of
luxuriant fur, that blinding grace which flashed its orange throat-patch
through the trees, and I realized I was sweating. For a moment I had
been that squirrel, eyes wide with terror, seeing fate bear down, and
powerless before the natural order of things.

The incident got the other squirrels singing again; but the confidence
was gone, and soon it was quiet. What dreams do squirrels dream, I
wondered, looking around. I saw that place more clearly then, having
been caught between a marten and its prey. I saw each spruce: its age,
its condition, the onslaughts it had borne; the beargrass coming up in
an opening; and down the trail a meadow that was yellow, white, and red
with sulphur plant, mariposa, and Indian paintbrush. Bees, flies,
spiders, and butterflies worked that little garden tucked among the
crowding trees. Countless forms of life beneath the soil and bark, in
tunnel, crevice, hole, and pocket, working unseen to sustain their
lives, and somehow, when all were added up, maintaining the forest as
well.

A flicker called, its loud _Klee-yer_ breaking the forest hush. Birds,
mammals, plants, insects--all hide together here, their lives so
skillfully embroidered that no loose thread exists that my mind might
grasp to unravel and understand the work.

The forest had once been a place that obstructed my view, a great blank
to stride through, a few hours of necessary blur before the high lake or
pass was reached. Now I was quite content to remain awhile beneath these
great-boled trees.

[_]
A forest, like the mountains themselves, supports various levels of
life. The floor and substratum are a great processing plant where
bacteria, fungi, and insects work, decomposing the plant and animal
litter, recycling dead and discarded tissue back to simpler organic
compounds, gases, and minerals, thereby providing sustenance for growing
plants. As spiders, shrews, wrens, and thrushes seem to know, there is
good hunting on the forest floor.

Just above the forest floor is the herb layer, a seasonal layer of
growth including flowers, mushrooms, grasses, and other small plants.

Above that grows the shrub layer, then the understory of young trees
awaiting their chance to take a place in the forest's canopy high above.
From the swaying canopy, exposed to the full force of sun and wind, to
the dim, moist floor, the forest provides a wide range of habitat.

Relatively few animals live in the treetops. The almost incessant motion
makes nesting too hazardous for birds. Red squirrels venture up to cut
cones in the canopy, but store their booty and make their nests farther
down.

In the mid-range between canopy and understory, goshawks and Cooper's
hawks nest. Woodpeckers, nuthatches, and sapsuckers forage on the tree
trunks and nest in cavities they excavate or appropriate. Red squirrels
and the nocturnal flying squirrels create a major traffic here, along
with the martens and owls that hunt them.

The understory and shrub layers house the greatest numbers of nesting
birds. Here the effects of storm and rain are minimized and protective
cover is greatest. Vireos, thrushes, warblers, hummingbirds, bluebirds,
flycatchers, and others can be found among the tangle of this sometimes
impenetrable layer.

The most populated area, the forest floor, supports an astonishing
abundance of organisms. Below the busy traffic of mice, shrews, and
larger animals is a bewildering array of insects and other
invertebrates. The attrition rate in the litter of the forest floor--a
continual battleground difficult to comprehend--is enormous. The smaller
the organism, the greater its numbers are likely to be. This humus-rich,
moist soil teems with bacteria, and a handful will contain surprising
numbers of small spiders, pseudo-scorpions and almost microscopic mites.

Each year some two to three thousand kilograms, dry weight, of falling
material litter an average hectare of forest. All this plant and animal
waste--twigs, leaves, limbs, fallen trees, feathers, hair, feces, and
carcasses--is processed by the armies of decomposers that thrive on the
forest floor. With the aid of larger creatures that break up the plant
and animal tissue, most microscopic bacteria are able to decompose from
a hundred to a thousand times their own weight every day.

Few trees die of old age in the forest. The seedling mortality rate is
necessarily high, since far greater numbers of seeds germinate each year
than can reach maturity. Of those that do, many fall victim to the
ever-present dangers of disease, insect infestation, windfall, stream
erosion, and fire. Insects alone present a formidable threat to trees,
for they have evolved every means of attack--chewing and mining leaves,
boring into twigs, eating cambium and heartwood, sucking sap, triggering
galls. If the insect world did not police itself, aided by spiders,
insectivorous birds and other animals, forests and other plantlife would
quickly fade before the chewing, boring, sucking horde.

[_]
Through the trees the light on Citadel shows the morning slipping by. As
I start to get up I see a garter snake sliding out into the dusty trail,
seeking the sun-warmed earth. Moving slowly, alert for danger, it probes
the air frequently with its sensitive tongue. But against the
lightcolored duff its dark shape offers a fine target, begging attack. A
chipmunk, watching from a nearby lookout stump, twitches its tail
nervously over its back, curious--perhaps suspicious--at the sight of a
snake. Very slightly the snake's head goes up, its tongue flickering.
For a few seconds reptile and rodent regard each other. Then the
chipmunk drops back soundlessly into its hollow stump, and the snake
lowers its head onto warm ground.

Some day soon, a sparrowhawk or weasel will interrupt the snake's
morning sun-bath. The snake will fuel bird or mammal for a time, as
mice, fledgling birds, and insects now sustain the snake. The chipmunk
too, rummaging nearby, lives in shadows of talon and tooth.

Until that time of sharp encounter, each has its own niche, a way of
life, a shaft of sun, and food enough.

                     A Walk in the Redcedar Forest

Climax! The word takes on a true significance here, among these
broad-based trees. When you enter this forest the road noise does not
follow far--as, when you walk into a cave and turn a corner, sound and
light are left behind. There is a surprising spaciousness, a feeling of
openness in a mature western redcedar forest. With scant understory and
the canopy so far above and everywhere complete, it seems like some
vast, high-ceilinged catacomb, pillared by the huge, shaggy-barked
cedars and the deeply scored trunks of the black cottonwoods. The floor
is strewn with fallen giants in magnificent disarray, uplifted roots
still grasping fractured rock.

A rainy day is a good time to walk a cedar trail, when the dull light
seems to shine from the wet moss, making the underleaves of devil's-club
and Rocky Mountain maple glow. Wind and rain, like light, penetrate with
difficulty the latticework of this canopy; thin lines of fog develop
over the bogs. The air is fresh with growing plants, snow-cold still
when the first spring flowers appear.

Fiddleheads of unfolding lady ferns line the trail in May, pushing up
from the hub of last year's leveled, lifeless fronds. Beds of trillium
shine their white, three-pointed flowers like flashlights in the dark
recesses. Unlike the small, hidden calypso orchid, which bears its
purple spikes and yellow throat low above the moss, the trilliums make
no secret of spring growth. They are bold, handsome plants, broad-leaved
and tall, with waxy white petals that tinge to purple in their
month-long bloom.

Moss covers everything. Boulders are green and weightless-looking,
resilient and topped with miniature forests of cedar seedlings. Ancient
fallen trees are disguised with blankets of moss, sprouting hemlock here
and there. The rich greens that characterize Glacier's summers seem to
begin here amid the moisture-glossed leaves of twinflower, bunchberry
and bead-lily.

Later, the spiders will spin thousands of kilometers of gossamer
filament among the trees. The orb-weavers will hang their webs high and
low, suspended in every opening. Walking through the forest then, you
will see shafts of sunlight whirling in the higher webs until they seem
like tops set spinning among the treetrunks.

Indianpipes, the "ghost flowers" that need no light to grow, will break
through the forest soil. Like mushrooms, with fruiting bodies that are
nourished by underground mycelia, these saprophytes absorb their
nutrients from a fungus that covers their roots.

Receiving an average of about 18 centimeters more annual precipitation
than forests east of the Divide, Glacier's redcedar-hemlock community
hoards its moisture. Its dense growth and the surrounding mountain walls
inhibit the circulation of drying winds. Mosses and ferns transpire
their moisture, which you can feel; place your hand close, and you will
sense a coolness like the air exuding from an ice cave. Draped from the
tree limbs are long filaments of squawhair and goatsbeard, black and
grey lichen strands that flourish in the damp air.

Except for the black bear, few large animals inhabit the deep forest.
Grizzlies find better forage in meadows or along the forest edge. Since
shade discourages shrubby undergrowth, deer and wapiti will search
elsewhere for browse. In summer, wapiti, grizzlies, and mule deer bucks
tend to wander up into high meadows.

Contrasted to the noisy, conspicuous birds of the prairie--meadowlarks
and bobolinks--birds of the forest seem elusive and secretive. Although
numerous, the varied thrushes, Townsend's solitaires, and Swainson's
thrushes are seldom seen; but when approached, they fly silently off and
are swallowed by the forest shadow.

There seems to be serenity in a mature forest, as though the struggle
for life is somehow suspended, the needs of the animals here less
urgent, muffled. The towering redcedar forest seems to be no battlefield
at all, but rather a monument to what Earth can do.

                        The Perpendicular Night

Behind Avalanche campground a trail leads back toward Lake McDonald
Lodge. I decided to follow it one June evening, to experience the
sensation of the deep forest changing into night. With the nearby
mountain wall intercepting the sun, dusk comes early to this valley. On
the prairie, night passes across the landscape in an even line,
forthright as a waxing tide; you can almost feel the globe in its
turning from the sun. There is reassurance in the night's coming, its
steady purple doming over the sky.

But here darkness seems to sprout from the earth. It collects beneath
the hemlock clumps, bridges the creekbottoms. It seems to flit from
place to place. You look about, uneasy, trying to catch it here or
there, but always miss its infiltrations. It captures the narrow
clearings when you look away; pockets of tree-darkness join together,
forcing the light upward until the tree-tops seem impossibly bright and
distant.

Through the trees I could see a dozen fires dance in the growing shadow,
wood-smoke and camp sounds filling the air. Turning uptrail, I felt a
reluctance to leave the presence of those fires--a senseless feeling,
but strong. A growing forest-dread impelled me almost physically
backward to those circles of firelight. I felt the need to be near a
fire, to be reassured by heat and light. Fire was our greatest friend,
our greatest weapon. With it we beat the long ages of ice and held the
forest gloom away. There was no harm here, only silence; yet the longer
I walked, with beard-moss hanging down like daggers all around, the more
I craved the comradeship of fire.

                                                    _Continued on p. 104_

    The Vital Predator

    The merciless law of predation might at first thought seem cruel;
    but the predator plays a vital part in maintaining the balance of
    the biotic community. Without the controlling factor of predation,
    prey species quickly enlarge their populations. If plant eaters are
    not checked, the resulting excess population exceeds the carrying
    capacity of the range. Food supply rapidly diminishes. In a damaged
    range, competition and stress result, usually culminating in a
    massive die-off through starvation and disease.

    Ironically, predators thus provide a service to their prey. First to
    fall to the predator are the old, the diseased, the unwary, and the
    young. By removing many young and old deer from a typical herd,
    cougars lessen competition among the deer for choice range, thus
    tending to keep herbivore numbers at parity with the land's carrying
    capacity. Only the strongest and wariest deer survive, ensuring that
    the fittest will continue the species. When man upsets this delicate
    balance--destroying predators in the hope of increasing numbers of
    game animals--the result is ecological disaster. In the 1930s, in a
    misguided attempt to "preserve" the whitetail deer herds of the
    park's North Fork area, many coyotes and cougars were exterminated.
    In 1935 alone, 50 cougars were killed. Relieved of the pressure of
    predation, the deer flourished. In a few years, however, the
    normally adequate range was severely overbrowsed. Suffering also
    from this imbalance were wapiti ("elk") and moose, ungulates that
    share the winter range with deer.

    Some predators are more specialized than others. The Canada lynx,
    for example, has oversize feet, an adaptation that helps it move
    across deep snow without breaking the surface. As a result, it is an
    efficient predator of the snowshoe hare, another large-footed
    animal. Relying on this adaptation, the lynx feeds almost
    exclusively on snowshoe hares. Consequently, its numbers inevitably
    fluctuate with the 10-year "boom and bust" cycle of the snowshoe.

    The coyote, on the other hand, is a generalized predator, exploiting
    whatever prey is currently abundant. Should mice or ground squirrels
    be in short supply, it will subsist on anything from grasshoppers to
    berries until favored prey again becomes available. (Animals that
    normally eat both plant and animal food are referred to as
    omnivores.) Generalized predators are thus better equipped to
    survive temporary ecological imbalances, maintaining their numbers
    at relatively consistent levels from year to year.

    Carnivores all, the animals on these pages illustrate various
    adaptations for capturing prey.

    [Illustration: The population of the Canada lynx, which is widely
    distributed in Glacier's coniferous forests, fluctuates in cycles.
    The lynx is abundant or scarce depending on the population condition
    of its chief prey, the equally cyclic snowshoe hare.]

    [Illustration: The cougar, which feeds primarily on deer, requires a
    large territory. Because of its strength, stealth, and speed,
    American folklore has given this wary cat a false reputation as a
    man-stalker.]

    [Illustration: The red fox depends largely on a well-developed sense
    of smell to locate its prey; it also relies on its keen eyesight,
    speed, and agility to capture mice, hares, birds, and whatever else
    it can run down or surprise.]

    [Illustration: To feed its demanding young, the Swainson's thrush
    hunts for insects along the forest floor and in the dense
    underbrush. This thrush relies on its secretive behavior to protect
    its nest near the ground from detection by other predators.]

    [Illustration: Armed with enlarged forelegs, the crab spider waits
    on or near flowers to ambush visiting bees, flies, or other insects.
    Its venom produces a quick kill, allowing it to attack insects many
    times its own size.]

    [Illustration: The spotted frog is a large-mouthed predator that not
    only eats water striders and other insects but also gulps down
    smaller frogs and small fish.]

    Protective Coloration

    To escape extermination, each species must in some manner foil its
    enemies. Protective coloration is one of the more common adaptations
    helping to do this. Most animals resemble their environment to some
    extent. The conspicuous markings of some, like the bitter-tasting
    monarch butterfly or the striped skunk, seem to function as a
    warning to prospective predators that it is in their best interest
    to look elsewhere for a meal.

    Some animals, such as the white-tailed ptarmigan and the snowshoe
    hare, have seasonal changes in plumage or pelage, wearing white in
    winter and brown in summer. Even predators, such as longtail and
    shorttail weasels, benefit from seasonal camouflage. Protective
    coloration makes them less noticeable to prey species and to larger
    predators.

    Many insects, too, change coloration with the season. Bright green
    grasshoppers of early summer become more brown with each molt,
    matching the changes in the surrounding vegetation.

    _Obliterative shading_ is especially important to animals that
    frequent more than one habitat. Seen from above, turtles match their
    dark background; from below, because of their lighter underbody
    shading they blend into the bright skylight.

    _Disruptive coloration_ aids in breaking up an animal's outline.
    Butterflies and moths commonly have disruptive wing markings. The
    distinctive shapes of eyes can be concealed. Eye coloration may
    mimic body color--as in the green katydid--or the eye may continue
    disruptive body markings.

    Ground-nesting birds are especially vulnerable to attack. Their eggs
    tend to be heavily blotched with earthy colors, making them less
    conspicuous. Chicks also carry these disruptive colorations on natal
    down.

    Most mammals, with coats of brown or gray, are inconspicuous when
    motionless. Deer fawns are endowed with speckled coats, mimicking
    the sun-flecked forest floor; this disruptive coloration, coupled
    with absence of scent and their instinctive "freezing" behavior,
    makes it difficult for predators to detect them.

    The whitetail deer not only uses its white "flag" to warn others in
    the herd of danger; it also allows a pursuing predator to use it as
    a target. When the tail is suddenly dropped--abruptly obliterating
    the bright white patch--the deer seems to disappear into its dim
    surroundings.

    Since overly conspicuous animals are prone to predation, natural
    selection favors development of appropriate camouflage.

    [Illustration: For such ground-dwelling birds as the white-tailed
    ptarmigan, camouflage is an important survival adaptation. The
    ptarmigan changes its plumage to match its surroundings: it is white
    in winter, speckled in summer. Moving slowly and refraining from
    flight, it is less likely than more-active birds to be detected by
    sharp-eyed, motion-conscious predators.]

    [Illustration: Birds that when hatched are covered with down and are
    able to move about freely are called _precocial_. They are less
    dependent upon their parents than are _altricial_ young, which are
    naked and helpless when they hatch; but they must rely heavily on a
    resemblance to their surroundings for survival during their first
    flightless weeks. This spruce grouse chick, which blends into its
    sunflecked forest-floor habitat, is an example of a precocial bird.]

    [Illustration: The bold disruptive pattern of the killdeer chick's
    plumage helps this precocial bird avoid detection in its
    open-prairie environment. This adaptation, coupled with the chick's
    instinct to freeze at the approach of danger, ensures that enough
    young will survive to perpetuate the species.]

    _Ursus arctos horribilus_: The Vulnerable King

    At the apex of the food pyramid, this great beast is unquestionably
    the king of Glacier's biotic community. Yet the long-range future of
    the grizzly bear is uncertain. With the grizzly exterminated from
    most of its former range--which once extended into the midcontinent
    and south into Mexico--its numbers have dwindled in proportion to
    its diminished range. Present concentrations in the contiguous
    United States remain in and around Yellowstone and Glacier National
    Parks. Probably fewer than 200 of these magnificent creatures live
    in Glacier National Park.

    Grizzlies are easily distinguished from the more common black bear.
    In addition to larger size and heavier build, grizzlies have a
    characteristic shoulder hump; long, conspicuous claws; and a broad,
    concave face that gives them a "dished-in" appearance. Fur is
    usually brown; like the fur of the black bear, however, color may
    range from black to yellowish. Light tipped hairs make the fur
    appear frosted, giving rise to the nickname, "silvertip."

    Grizzlies, popularly considered arch predators, are more accurately
    described as omnivores. Carrion, grasses, cow parsnip, and several
    species of berries, bulbs, and tubers make up a grizzly's diet,
    along with insects, small mammals, and an occasional ungulate that
    it can catch. As a result, grizzlies play several roles in the
    biotic community, functioning as herbivore, scavenger, and predator.

    Ranging widely in all life zones, grizzlies follow the spring
    snowmelt up to the alpine meadows, returning to lower elevations to
    hibernate from November until April. One to three cubs are born in
    midwinter during hibernation. Since the maternal bond lasts two
    years, a sow will accept a mate only every other year. Mortality of
    subadults is high, resulting principally from competition among the
    bears themselves. As with most animals, range--habitat--appears to
    be the limiting factor of grizzly populations.

    The grizzly is normally shy and fearful of man--but highly
    unpredictable. Wounded or sick bears, sows defending cubs, young
    adults, and bears that have become conditioned to human scent are
    the most dangerous. As humans continue to encroach on grizzly
    territory, odds of confrontation also increase. Recent fatalities
    and personal injuries inflicted by grizzlies pose a vexing problem
    to the National Park Service, which is charged with visitor safety
    on the one hand and protection of the park's remaining grizzly
    population on the other. Continuing study of grizzly ecology and
    increasingly enlightened bear management programs will, it is hoped,
    allow man and bear to co-exist in a wilderness both require.

    [Illustration: Grizzlies are fond of succulent spring grasses.]

    [Illustration: Traversing all life zones in the park, the grizzly is
    a true opportunist, eating anything from ants and berries to
    wapiti.]

    [Illustration: Seldom will a grizzly exceed 225 kilograms in
    Glacier. This is a young adult.]

    Bald Eagles and Kokanee Salmon: A Recent Gathering

    In 1916 the kokanee salmon, a small, land-locked form of the Pacific
    coast species, was planted in the Flathead drainage. With the first
    planting augmented by additional stockings, the fish thrived in
    cold, deep Flathead Lake, and, to a lesser extent, in Lake McDonald.
    The salmon fed almost exclusively on zooplankton.

    By the mid-1930s, salmon runs were becoming established. The outlet
    of Lake McDonald provides an ideal spawning site for the salmon. The
    fast-flowing water is clear, cold, and shallow, and the creek bed is
    gravelly.

    Averaging 0.3 meters in length and weighing less than a half-kilo,
    the 4-year-old adult salmon cease feeding and begin to migrate. Many
    thousands swim the 100 kilometers from Flathead Lake to McDonald
    Creek. Males appear in the creek first, arriving in late September,
    and are soon followed by the females.

    Using her tail to dig a redd (a shallow nest depression), the female
    deposits about 650 eggs. After fertilization by the male, the eggs
    are covered over. The adults die within three weeks after spawning,
    their bodies exhausted from the rigorous migration journey and the
    weeks-long lack of sustenance.

    Egg fatalities are high, due to stream erosion and disturbance by
    other spawning salmon. Hatching in late March, the fry work their
    way out of the gravel and migrate downstream.

    Attracted to the 75,000-150,000 salmon concentrated in a 3-kilometer
    stretch of shallow water, bald eagles begin gathering at McDonald
    Creek in October. It is not known where the eagles come from or
    where they go after the spawning run. Glacier has fewer than 20
    summer-resident bald eagles, and these are distributed among the
    remote lakes of the North Fork area.

    In 1939, 37 bald eagles were counted along the creek. By 1969, 373
    were reported, representing approximately 10 percent of that year's
    estimated winter population for the contiguous United States. Since
    1960, the count has averaged 240 birds. (In 1977 there were 444.)

    Eagles feed by swooping down to pluck salmon from the water or by
    wading out to grab a fish stranded on a shallow riffle. An eagle may
    consume as many as six fish a day. Immature birds are not as adept
    at catching fish and may harry adults or other immatures into
    releasing their catch.

    [Illustration: From its vantage point, this mature bald eagle
    examines the waters of McDonald Creek. Average weight is 5.7
    kilograms; average wingspan is 2.2 meters. Females are slightly
    larger than males.]

    [Illustration: This immature bald eagle lacks the familiar white
    head and tail of the adult birds. It will not acquire those markings
    until it is several years old.]

    [Illustration: Breeding male and female kokanee salmon are easily
    distinguishable; as spawning time approaches, they change
    appearance. The dark gray backs turn red; heads become green, and
    the males develop humped backs and hooked jaws.]

    [Illustration: Swooping upward with a fish, a mature eagle heads for
    a convenient perch to consume its catch. A strategically located
    tree may contain 30 birds.]

    A Triumph of Many Colors

    Grassland, meadow, tundra, or any other area in Glacier suitable for
    plant growth and supplied with abundant sunlight produces an
    extravagance of wildflowers. This display of various shapes and
    colors is neither an accident nor a mere decoration of nature. Nor
    would Earth's recent explosion of mammal and bird species have been
    possible without the evolution of flowering plants.

    Two hundred million years ago, early in the Age of Reptiles,
    angiosperms (flowering plants) had not yet evolved. Plant
    reproduction still relied on spores and cones. Then, during the
    Cretaceous Period, the last sediments were being laid down in the
    inland sea that covered most of Montana. (It was these sediments
    that the ancient Precambrian rocks of Glacier's mountains later
    overrode, forming the Lewis Overthrust.) During this period the
    evolutionary miracle occurred: flowering plants--grasses, vines,
    shrubs, broadleaf trees, wildflowers--inherited the Earth.

    The timing was important. As Earth's tropical climate gradually
    changed to temperate extremes during this period, the domination of
    cold-blooded dinosaurs ended and the moisture-demanding coniferous
    forests that had covered the earth in green monotony began to
    shrink. Angiosperms provided a solution to the ecological void:
    grasses and forbs grew where trees no longer could. Most important,
    relationships evolved between this new class of plants and the
    relatively few species of insects then existing.

    Insects began to use the pollen of flowering plants; the
    angiosperms, in turn, evolved bright petals and nectar that
    exploited visiting insects for the plants' own reproductive
    purposes. This partnership allowed insects to diversify rapidly,
    evolving new, specialized forms such as bees, moths, and
    butterflies. As a result, predatory forms of insects and arachnids
    also rapidly diversified.

    The most dramatic change, however, involved warm-blooded birds and
    mammals, whose high rates of metabolism required high-energy fuels.
    Unlike gymnosperm seeds, which contain no protective covering,
    angiosperm seeds are surrounded by a fruit. The development of these
    highly nutritious seeds, and the attendant explosion of insect
    species, ensured survival of the newly evolved birds.

    As birds diversified into seed-eaters, insectivores, and carnivores,
    mammals, then uncertain little ratlike creatures darting among the
    feet of dinosaurs, began a rapid rise to dominance; grasslands
    promoted an explosion of herbivorous and carnivorous species.

    The evolution of angiosperms, and the animal revolution it made
    possible, came with amazing speed. Most significant, it was a vital
    first step upon which the meteoric rise of man depended.

    [Illustration: Indian paintbrush is common at all elevations below
    tundra. It may be white, yellow, orange, pink or red. The actual
    flowers, inconspicuous and green, are surrounded by brilliantly
    colored bracts. Semi-parasitic on other plants, paintbrush is
    normally found growing in conjunction with other wildflowers; its
    roots steal sustenance from neighboring plants.]

    [Illustration: Yellow stonecrop, widely distributed in forest and
    scrub-forest zones, is one of the park's few plants having succulent
    leaves, an adaptation that helps it survive in such situations as
    dry, rocky outcrops.]

    [Illustration: The Calypso orchid grows in the cool, shadowed forest
    where light is dim. It lives in partnership with certain fungi that
    exist about the orchid's roots and seem to help nourish it.]

    [Illustration: Silky lupine, a legume, has nitrogen-fixing nodules
    on its roots, thus allowing it to grow in nitrogen-poor soil. It is
    widely distributed in grassland and forest communities.]

    Fire Succession: Key to Continuity

    Most of Glacier's fires are lightning-caused. Strikes may flare up
    immediately; or fires may smolder in the forest duff for days until
    fanned into flame by wind. _Ground fires_ may race through the
    forest understory, causing minor damage; or they may bridge the
    understory and reach the canopy, thus becoming rapidly spreading
    _crown fires_. Under certain conditions, uncontrollable infernos may
    develop, generating terrific winds and heat. These rare
    conflagrations are called _fire storms_.

    Every type of forest habitat has _climax vegetation_--trees and
    shrubs that are best suited to the site and thus maintain themselves
    indefinitely if not disrupted.

    After a major fire, habitat conditions are usually so altered that
    the site must pass through several _seral stages_ before conditions
    are such that climax vegetation can return. A _sere_ is a series of
    plant communities that follow one another in orderly fashion until
    climax conditions are again reached.

    [Illustration: Lightning fires occur most often during the hot, dry
    weeks of late summer.]

    [Illustration: When the forest is dry, lightning often causes quick
    flare-ups.]

    [Illustration: The forest may continue to burn for days after the
    main conflagration has passed.]

    [Illustration: After a major fire, sun-loving grasses, shrubs, and
    wildflowers quickly invade the former forest. Deer and wapiti
    benefit from these new food sources.]

    [Illustration: Lodgepole pine, a pioneer species quick to take over
    burned areas at lower elevations, grows rapidly. These trees are
    five years old.]

    [Illustration: This is a Glacier National Park forest 80 years after
    a major fire.]

Sudden hammering made me jump. Above the forest darkness, a pileated
woodpecker leaned out from a high larch snag, braced against the trunk
by its specialized, stiff tail feathers. This was the first time I had
seen this big white-and-black bird, the "cock-of-the-woods." There was
ample evidence of his work: the deep, oblong excavations in the trunk
and the pile of large wood chips at its base, both characteristic of
this species. Again he hammered, and I could see the chips falling.
After a little edge-work around the hole, he extracted a grub and flew
off, yammering against the advancing dark.

Near a stream I stopped to sit down, to listen to the water and maybe
catch sight of some small animal. Across the narrow defile, from a slope
dense with young hemlock, came the buzzing note of a varied thrush.
Several notes followed, all on a different pitch, all drawn out, level
and clear; the quality was pure but songless, disjointed, deliberate,
like someone testing the reed of a strange woodwind. There seemed no
gladness in the heart of this thrush. The song was dark, haunting,
lonely.

On the trail ahead I could make out a bird hopping rapidly along. After
passing the spot I could hear its song. There couldn't be a hundred
meters between us, yet it seemed to be coming from a great distance. I
listened for as long as it would sing. I tried to hear it for what it
was, a male Swainson's thrush proclaiming its territory. But the
ethereal, flute-like phrases seemed an evensong made not for man's ears
but only for the forest itself.

I hurried on after the bird had ceased. It was getting dark beneath the
trees, but I was beginning to be aware of creatures underfoot, the mad
dartings of shrew and vole, more imagined than seen. When a deer mouse
jumped away I got out my flashlight. Soon the beam caught a woodrat
sitting atop a fallen log. The light didn't bother him in the least; as
I approached, he picked up his bushy tail in his forepaws. Whiskers
twitching, he looked more caricature than real. Then he bounded off the
log with graceful, arching hops, and disappeared into the night.

Against a patch of sky that appeared in a clearing, I could make out
bats, circling and dipping like swallows. Locating a hovering moth, I
kept the light beam on it until it vanished into a furry streak of
silence. It was time to head back.

By now it had become utterly dark within the trees, a moonless,
sightless, alien world, given over to the marble-black eyes of the small
night mammals and the creatures that hunt them. I thought of the
strange, unseen societies of the flying squirrels, the nocturnal
counterparts of red squirrels; of the great-horned owls, inspecting the
same ground the goshawks scanned during the day. Perhaps a foraging red
fox moved through the darkness nearby, or a coyote on night patrol.

The flashlight beam probed ahead along the trail. The exposed roots were
given unnatural shading and they seemed to thicken and squirm as I
approached. On either side the tree trunks appeared to step backward
from the dim glow of the light. I felt lost in this night, thinking of
the great darkness in all the timbered ridges that ran westward from the
Divide. In this vast cathedral of crowded tree and peak, night was stood
on end, the stars shrunken to a circle overhead, as if seen from the
bottom of a well. Mouselike, shivering, insignificant in this
wilderness, I scurried back to find a fire and fill my empty senses with
its heat and snap and light, holding off the fright of night and
thinking of tomorrow's sun.

Scrub-Forest

The crowning beauty of Glacier--the high, cirqueheld meadows that scent
the wind with wildflower and waterfall--belongs to the zone of
scrub-forest.

At Logan Pass you are introduced to the highlands. Here an exquisite
upland basin holds the Hanging Gardens, a wildflower-clothed gradient
laced with stair-step bogs and lines of wind-bent subalpine fir. In the
dawn sun, before the first engine noise, it shines unbroken, dewbright
and sagging like a spider web secured to the circle of surrounding
peaks.

This is the region the hiker remembers best. The tall mountains wear
this zone close to the cliffs, and the trails encounter it near the
passes or follow it for long, level stretches, as along the Garden Wall.
I remember Preston Park and Fifty Mountain, the fire-touched bench of
Granite Park and the first sight of Sperry chalet, built on a brow of
rock at the upper reach of trees. But most of all I remember the
terrible waterfall that becomes Bowman Creek, the plunge of nearly a
kilometer that drains the magnificent upland bench called
Hole-in-the-Wall.

                            Hole-in-the-Wall

September. The season is growing late, the meadow-rue dying and the
leaves of the wild strawberry failing at last. Everywhere the red
contagion of autumn surrounds the vital green. The lower valleys have
lost the whistle of ground squirrels. They sun themselves no longer
these late, mild days. Ripe, sluggish, and hawk-vulnerable, they sensed
the need of hibernation.

It has been eight years since I last visited Hole-in-the-Wall, but I
retain its dimensions and hear its dozen waterfalls at will. Once you
have seen this basin you have a measure by which to judge the high
country and a thirst for the meadows at tree-line.

In Glacier, treelimit ranges between 1,850 and 2,300 meters, depending
on local conditions. The upper limit of tree growth--rarely an even,
horizontal line--is generally an indistinct band running erratically
across a mountain's face: a tension zone reflecting variations in wind
and sun exposure, degree of slope, snowpack accumulations, and the
presence of adequate soil and water.

Subalpine fir, whitebark pine, and Engelmann spruce do not relinquish
easily their upward climb; where conditions become severe, their growth
is retarded and their stature dwarfed. Deformed and pruned by wind,
their leaders winter-killed when they outreach the protection of the
winter snowpack, trees become shrubs, forced to hug the ground. Size
belies age in these elfin forests, or krummholz, where the growing
season is painfully brief and progress is always uncertain. A twisted,
gnarled little bush, more snag than live branch, bearing a single cone
or two, may be senior by a century to the giants of its race in the
valley below, which yearly shower the ground with an abundant crop of
cones.

This time I will come from Goathaunt, passing Lakes Janet and Francis,
reaching Brown Pass from the east, and camp in the spectacular garden
between Brown and Boulder Passes.

Meadows and rock slides break the forest as the trail gains elevation
and distance through the valley. The spruce and fir thin out rapidly at
the valley head, the trail climbing the grassy slope to low, broad Brown
Pass. Below the pass is Thunderbird Pond, which receives the meltwater
from a glacier high on a shelf of Thunderbird Mountain and is bordered
by a low jungle of willow. In the water stands a bull moose, its heavy,
fully formed antlers ready for the season's impending business.

I was hoping again to see Cassin's finches and Audubon's warblers on the
pass; but the fir grove is quiet. Sitting down to rest and listen, I
become aware of a strange silence. No birds sing or flit among the
trees, no alarms pass back and forth among alert ground squirrels. There
is no wind--an odd condition for the Continental Divide. This place
seems to be holding its breath. High overhead, a veil of cirrus cloud
arranges long spears across the sky.

Moving off the pass, along the dome of Mt. Chapman, I experience anew
the old excitement of this high country. Abruptly the gorge of Bowman
valley opens up, revealing the twisting blue snake of Bowman Lake far
down the narrow, cliff-imprisoned valley. Here again are the northern
titans--Numa, Peabody, Boulder, Thunderbird, and Rainbow; and Carter,
with its high glacier baring blue ice teeth to the sun.

It is not the climb that makes your heart pound now; the trail is
suddenly narrow and cliff-defiant, cut by the plunging waters of
snowbanks far above. These are splendid peaks, unmatched in a land of
muscled, brutal earth. Even the air seems to retain the scent of glacier
work.

At last the view of Hole-in-the-Wall, a staircase cirque excavated
between the gigantic spread ribs of Mt. Custer. The slopes of beargrass
are seed-spotted and gaunt now, the white fullness gone. Western
pasqueflowers have accomplished their magic transformation; known in
this season as old man's beard, they nod their tufts of grizzled
seedhead silk in the wind. Red and yellow monkeyflowers bloom yet,
crowding along the many stream courses, and waterloving sedges and
mosses surround pools of collected water on the broad horseshoe tiers.

A spur trail drops down into the campground on the last ledge. Through a
cleft in its lip plummets the gathered water of the basin. From the
valley below, the waterfall appears to be springing from a hole in the
headwall, giving this basin its name. Down, down, down, roars the water
where once a mighty glacier ground its teeth.

I leave until later the making of camp; by now the sharp shadows of
Boulder Peak stab the valley forest and are beginning the upward assault
of Thunderbird.

Around the basin headwalls, last winter's snowbanks remain formidable.
Snow caves send out meltwater torrents. Glacier lilies and patches of
spring beauty line their fringes. Pasqueflowers bloom in pockets. Here,
among the asters of August, bloom also the first flowers of spring,
shooting up as the snowbanks shrink, making these spots of snow-free
ground a patchwork of May and July, August and June. The shrubs that
line the furious water are willows, still bud-swollen this tenth day of
September. The coming days will bring a sharp surprise.

Winter will soon stop the melting of this snow. Could it be that I am
seeing the first year of a reawakening ice age? If so, each year the
snowfields would grow thicker and broader, connecting the shelves into
one ice mass again, lilies and willows entombed, the summer heat failing
to rescue them, until the ice at last began to slide, stripping the soil
and once more plucking at living rock.

Then these dwarfed fir, which cling precariously to the cliffs and hide
behind the backs of boulders, would be in more danger than they were
from their recent antagonists. Engulfed by ice, they would know the
shearing wind no more. Their skeletons would rain down into the valley
below, signalling another long forest retreat. But they have waited out
the mountain ice before and would send their seeds again to this valley,
changed however it might be, as they have always done.

Evening brings out two sleek mule deer does. As they graze, their large
ears stand erect, sorting out the lesser sounds from the ceaseless roar
of water. Both raise their heads and point their ears, statue straight,
at the scuttle of a porcupine. A noise among the rocks draws a backward
glance and focus of those ears. I would like the sensitivity of such
fine equipment, to hear what deer have always heard.

Setting about the business of camp, I wonder about those animals that
watched me for a while, then moved off, having seen a tent go up before.
With the appearance of the moon the wind increases and they test the air
more often now. Do they have visions of cougar or grizzly with every
snap the wind delivers?

In summer these high meadows see a surprising variety of animal life.
Briefly out of hibernation are marmots and the handsome golden-mantled
ground squirrels. Mice, voles, shrews, and woodrats run among the
shadows, feeding on the season's feast of seeds and insects. A nightmare
for these are the fierce little weasels that haunt the rocks.

Tracks of cougar and wolverine are sometimes seen, often teasingly
fresh; to glimpse either of these elusive predators is to taste the
finest wine of wilderness.

Before the berry season, grizzlies grub the meadows for the tasty bulbs
of glacier lilies and the tubers of spring beauty; often distracted by
the scent of a ground squirrel in its burrow, they sometimes make a huge
excavation for a small reward.

White-crowned sparrows sing in July from the low tops of the battered
trees, though their nests are on the ground below. Grey-crowned rosy
finches patrol the drier ground for seeds while water pipits hunt
insects in the wet areas. High above, a golden eagle scans the basin
again, circling slowly before following a ridge south to sight another
likely slope in its 10,000-hectare territory.

The moon shines through the tent top. The wind, blowing more violently
now, shivers the nylon and interrupts the voice of the waterfall. I have
followed the pasqueflower run from the April prairies here to its
highest bloom near treeline. I think about the triangular seed pods of
the glacier lilies, colonies of steep-throated blue gentians, and the
season's last glory of goldenrod. Indian paintbrush, from white to fire
red, blazes the slopes that light the fringes of sleep.

I awake to a determined rain, the moon gone and the tent shuddering with
wind-blast. I try not to think of the steel-cold air, and slip into a
fitful sleep that seems an endless treadmill of rocky trail.

Stiff and unrefreshed, I look out into the dawnless morning. The tip of
Thunderbird is detached from its base by grey clouds swirling at its
throat. A wave of sleet slants down, dancing on the rocks, chanting