The Forests and Wildflowers
Our continent has a variety of climates, and each
climatic area has its appropriate vegetation. Generally, the interiors
of continents do not have forests, but have grass or desert vegetation.
The most luxuriant forests develop near oceans where climate is
sufficiently moist. This is true of other continents as well as North
America.
The differences in the general character of our
natural vegetation from coast to coast and border to border are apparent
despite three centuries of man's disturbance in the East and one century
in the West. Sizeable samples of some of the many kinds of original
vegetation are preserved in national parks and monuments. These are
precious remnants of our plant heritage that become more valued year by
year in proportion to their scarcity elsewhere.
The mild, humid climate of the northern half of the
Pacific slope is unusually favorable for forest growth. The most
luxuriant of the western forests developed here in unbroken stretches.
The forests that girdle the Olympic Peninsula represent the best
development of this evergreen forest domain. Its ultimate composition is
of western hemlock and western redcedar in dense stands, with trunks
commonly 4 to 6 feet in diameter and 125 to 200 feet tall. Their crowns
shut out most of the sunlight, but enough gets through to the bottom of
the forest for the growth of mosses and ferns. Shrubs grow dense and
tall, in places becoming almost impenetrable to hikers. Fallen trees of
all sizes soon are enveloped by the lush growth in the damp shade, and
in time return to the soil through decay.
Hemlock and redcedar seedlings take root in the
forest litter or on prostrate, moss-covered trunks. They are able to
live in the deep shade. The most hardy of them outstrip their rivals,
and when a vacancy occurs in the forest canopy their growth speeds up.
Thus a forest of hemlock and redcedar is maintained. This is the climax
forest in the lowlands of the northwest coast. It is the kind of forest
the climate here will produce and maintain in the absence of
interference.
Interference has been the rule, however, both before
and since the coming of man. Therefore, the climax forest is less common
than the subclimax in which Douglas-fir is the dominant tree. Forest
fires have repeatedly exposed the forest floor to sunlight and thus
allowed the development of Douglas-fir, by far the most abundant and
widespread tree in northwest forests. In the regeneration of a forest
after fire, logging, or other disturbance, it is Douglas-fir that is
ever present.
The northwest coast is an evergreen land. This may
not be apparent in summer, however, when all plants are green. Not
counting the numerous mosses that are always green, there are 73 species
of evergreen plants on the Olympic Peninsula.
RAIN FOREST
An extraordinary forest has developed along the
western slopes of the Coast Range where moisture is available in the
greatest abundance. The most typical and beautiful expression of this
coastwise forest is found in the western valleys and on the coastal
plain of the Olympic Peninsula. It is the most luxuriant growth in any
temperate climate and may properly be called a rain forest. This
temperate-climate rain forest, however, is not like the rain forests of
the hot, superhumid tropics. Here, there are tall conifers instead of
broad-leaved trees; there are mosses and ferns on the ground instead of
an understory of vines.
DRAPERIES OF CLUBMOSS HANG FROM LIMBS IN THE RAIN
FOREST.
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The rain forest is principally distinguished by the
presence of Sitka spruce. This tree grows only in a narrow belt along
the coast from northern California to Alaska. The other trees of the
rain-forest community have much wider distribution.
The trees of this forest are among the largest in the
world. Many of them have trunks that exceed 10 feet in diameter at 4-1/2
feet above the ground, and are up to 300 feet tall. The largest known
trees in the park for the most common species are: western redcedar, 21
feet 4 inches in diameter; Sitka spruce, 13 feet 4 inches; Douglas-fir,
14 feet 5 inches; western hemlock, 9 feet; and Pacific silver fir, 6
feet 10 inches.
A visit to the rain forest offers a surprisingly
enjoyable experience. Although it is possible to drive through some
sections, this provides only a view of the trees. A forest is more than
a stand of treesit includes animal life, smaller plants, and
micro-organisms, such as bacteria. All these serve the forest and in
turn, their well-being depends upon the forest. They form the forest
community.
Splendid examples of rain forest may be seen in the
Hoh, Queets, and Quinault Valleys, but the Hoh Valley is the most
accessible. A paved road runs 19 miles up the Hoh from U.S. 101, ending
7 miles inside the park boundary where a National Park Service
campground has been developed. The Hoh River Trail starts just beyond
the nearby visitor center. It extends 18 miles to Glacier Meadow, close
to Blue Glacier on Mount Olympus. Approximately 12 miles of it is in
rain forest along the valley bottom. Only a small fraction of this
distance need be traveled, however, to see the forest.
Unexpectedly, one finds this forest beautifully
luminous. It is filled with soft, green light that drops down where it
can find room between the towering spruces and hemlocks. In the lower
levels of the forest it filters through the translucent leaves of the
vine maple and bounces from one green surface to another. Nature, in an
exuberant mood, has lavishly decorated this forest with mosses and
clubmosses. Moss carpets, with patterns of Oregon oxalis and beadruby,
cover the forest floor. The same material upholsters fallen trees and
the trunks of those standing. Mosses ascend to the very tops of
some of the tallest trees. Arched trunks of vine maple are cushioned
with them. Curtains of clubmosses hang from the same archways,
separating one green forest room from another.
The forest cycle from seed germination to death of
giant trees and their return to soil may be seen here in the course of a
short stroll. This is a cycle endlessly repeated. No part of it is
disturbed by man. Trees felled either by uprooting or by breaking of the
trunk are scattered everywhere in various degrees of decay. Rain-forest
trees have shallow but widespreading roots. To obtain nourishment, there
is no need for deep roots where water is available in dependable
abundance. But shallow roots in saturated soil do not always anchor
trees firmly enough against storm winds.
MOSS AND BEADRUBY PATTERN ON THE FLOOR OF THE
RAIN FOREST.
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Though dead and prostrate, the fallen trees still
have an important function in the forest. They are soon accepted into
the forest-floor community and become covered with lichens and mosses.
Various fungi and bacteria attack them from within. They become
nurseries for spruce and hemlock, whose seedlings prefer rotting wood.
The most vigorous seedlings send their roots down
the flanks of such old nurse logs, if big enough, will last until the trees they
foster grow to large size. Colonnades of huge trees may thus be seen
straddling old moldering logs. Seeds may even take root upon a broken
stump 12 feet or more above the ground. The roots reach the soil after
creeping down the full length of the stump. The result, when the stump
rots and crumbles away, is a tree standing on stilts. Thus the forest is
regenerated. New life compensates death. There is neither increase nor
decrease in total amount. What is dead eventually returns to soil and
feeds the living. This is brought about through the work of
saprophytesplants without chlorophyll, the substance which gives
plants their green color. They must obtain their food already made and
are content to take it dead. Many of these are mushrooms and other fungi
with colorful and beautifully shaped fruiting bodies. No better
description of their function in the forest can be found than that
written by Donald Culross Peattie.
Breaking up the debris of what was living, releasing
the precious materials in it, these fungi, and certain bacteria,
retrieve the vital elements from what would otherwise be a permanent and
cumulative and ultimately disastrous loss. They are part of what we call
decay, but they are as much a part of life. They turn over its wheels. . . .
THE SHELF FUNGUS IS ONE OF THE NUMEROUS ATTRACTIVE
FUNI.
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MOUNTAIN VEGETATION
A visit to Olympic is not complete without at least
one trip into the high country. Aside from the numerous trails that lead
up into the mountains, there are two high country areas that may be
reached by car. These are Hurricane Ridge and Deer Park. Whether the
trip is made on trail or on road, an understanding of the changing
pattern of plantlife will make it more enjoyable.
The climate at the top of a mountain is unlike that
at the base; accordingly, the plants are different. Plant scientists
have found that these vegetation differences on a mountain are similar
to the changes seen between the equator and the poles. Generally
speaking, each 100-foot rise in elevation is equivalent to about a
20-mile distance north. Although the change may be gradual, there are
distinguishable belts of vegetation on a mountain. These belts are
called life zones and have names that indicate their correspondence to
zones between the equator and the poles.
RED ALDER IS THE FIRST TREE TO GROW AT THE EDGE OF THE CHANGING COURSES
OF THE RAIN FOREST RIVERS.
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Altogether there are four life zones in the Olympic
Mountains: Transition, Canadian, Hudsonian, and Arctic-Alpine.
The vegetation of the last three is similar to that of regions to the
north at lower elevations, as indicated by their names.
The Transition zone in the Olympics is the lowest. It
is intermediate between southern and northern vegetation. The lowland
forests, including the rain forest already described, are in this
zone.
The next two zones also are forest, but somewhat
different. The highest, or fourth, zone is treeless. The boundaries
between the forest zones here are not sharp; it is difficult to know
exactly where one ends and the next begins. This merging of forest zones
in the Olympic Mountains may be due to the equable temperature
extending well up the mountain slopes.
The Canadian zone should be apparent when an
elevation of 2,000 feet is reached. The forest of this zone is somber
compared with that of the Transition zone. Although it has many kinds of
small shrubs and herbaceous plants, it lacks the striking greenness of
the Transition forest. Western white pine and Pacific silver fir have
entered it. Western redcedar is absent, while Douglas-fir and western
hemlock remain. There are numerous saprophytes on the forest
floormost of them flowering plants such as pinedrops, Indian-pipe,
and coralroot.
The Hudsonian zone is next, and is the highest one
having forest vegetation. Around 3,500 feet elevation there is a
mingling of Canadian and Hudsonian trees. Some trees of the Canadian
zone are still found, but some different kinds are included in the
forest composition. The characteristic Hudsonian zone trees are mountain
hemlock, Pacific silver fir, alpine fir, and Alaska-cedar. The
last-named has typical cedar foliage. Its branches and twigs droop as if
they were wilted. Trees in this zone are much smaller than those at
lower altitudes and become still smaller with every upward step. At the
uppermost fringe of tree growth the winds hold them close to the ground
as deformed growths. This is known as krummholz, a German word
meaning "crooked wood." The name is applied to stunted forest commonly
found in alpine regions. Timberline in the Olympic Mountains is
generally at about 5,000 feet, which coincides with the height of many
of the ridgetops. The beginning of the Hudsonian zone is the beginning
of the high country. The sky is bluer and in summer an alpine fragrance
adds zest to the air. The forested slopes give way, in depressions, to
meadows that are brilliant with wildflowers in summer. Basins carved by
snow and ice hold numerous mountain lakes, with streams flowing into and
out of them.
THE CANADIAN AND HUDSONIAN LIFE ZONES ARE REPRESENTED
IN THE RESPECTIVELY HIGHER FOREST BELTS THAT LIE ABOVE LUSH RAIN
FORESTS.
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The Hudsonian meadows, in depressions above 3,500
feet, are knee-deep in grass in July and August, and flowers form a
medley of color. Aster, pedicularis, arnica, shootingstar, cinquefoil,
and false hellebore are among the conspicuous flowers there.
Stream margins and marshy ground are preferred by
such plants as marshmarigold and globeflower.
Higher in the Hudsonian zone there are prairielike
meadows where flowers bloom in profusion. Extending 60 miles across the
north and east sides of the park there are thousands of acres of this
meadowland on the ridges. Hurricane Ridge is in the midst of this and
presents some of the finest flower displays. Some slopes in early summer
are white with avalanche lilies, one of the most abundant and
widespread of the mountain flowers. Near timberline they grow
among the trees, as well as in the open. Other meadows are yellow with
pure stands of glacier lily, one of the earliest of spring flowers.
Impatient with winter, it pushes through the thinning snowbanks. Where
soil is deep, subalpine lupine blooms profusely. Among the most common
and conspicuous in rich meadows are larkspur, buttercup, cinquefoil,
paintbrush, arnica, tiger lily, and mountain buckwheat.
MEADOWS AND CLUSTERS OF TREES OF THE HUDSONIAN
ZONE.
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Several plants found in the mountains in the
northeast part of the park, where rainfall is lighter, are more typical
of the hot, arid lowlands of eastern Washington and Oregon. Some of
these are nodding onion, woolly eriophyllum, and barestem
lomatiumtheir presence in the mountains may be due to the fact
that the broad ridgetop meadows in the northeastern part of the park
are remnants of a lower plain where these plants grew before the Olympic
Mountains had risen to their present height. As the mountains were
pushed up, these plants could have continued to grow and reproduce
despite changing conditions.
On hillsides where the rock has weathered only into
chips, or where little soil has formed, carpets of spreading phlox and
rosettes of Lyall lupine are most conspicuous in early summer. Some
plants grow on talus slides, on rocks broken and tumbled from peaks
above, and on rocks laid bare by retreating glacial ice. Lichens and
mosses, pioneers among plants, etch the rock with weak acids and thus
start the slow conversion of rock into soil. Some flowering plants are
pioneers, too. Common ones growing in crevices and soil pockets among
the rocks in the Hudsonian zone are smooth douglasia, alumroot, and
bluebell. Eventually, a flowered meadow or forested slope
develops where first there was only bare rock.
The Arctic-Alpine zone is the region above
timberline. It corresponds to the arctic meadows of northern Canada. In
the Olympics its lower limit is about 5,000 feet and its upper limit is
the tops of the peaks.
It is a harsh environment. Its shallow soil and
rocks, its wind and prolonged snow and cold exclude all but the hardiest
perennials. Annuals cannot live there. One growing season is too short
for a plant to start from seed, complete its vegetative growth, flower,
and ripen its seeds. Many of the plants are surface plants, such as
mosses and lichens, which do not produce flowers. But even the flowering
plants hug the ground. Their over-wintering buds are at or below the
ground surface. It is a struggle for moisture and against time. Only low
perennials, having small, tough leaves covered with hairs or wax, are
able to survive. These properties help protect the plants against loss
of water.
There are 8 kinds of mountain plants in the Olympics
that are not known to grow anywhere else. It appears that
these plants grew in the Olympic Mountains before the ice came and were
able to survive on ridgetops that remained free of glacial ice during
the long cold periods. They are thus relicts from preglacier time. None
of them are trees and only two are shrubs. All the rest are herbs.
Several of these, among which piper bellflower and Flett violet are
especially attractive, may be found on Hurricane Ridge and on the upper
slopes of Mount Angeles.
Snow is vital to mountain flowers. It provides most
of the moisture for their growth and governs the length of the growing
season. Spring flowers appear earliest where the snow melts
first. Where snow piles up deeply, it may not melt completely till
midsummer or may melt too late for plants to complete a season's growth.
On northern slopes the snow may remain all summer, and there can be no
growing season.
The high country has many floral patterns, which
change as the seasons progress. The flower displays are usually best
around the middle of July. Flowers of spring, summer, and autumn are
blooming then, according to the progress of the seasons in different
elevations and habitats.
ALPINE FIR GROWS NEAR TIMBERLINE.
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