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.
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 4½ 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 trees—it
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.
[Illustration: MOSS AND BEADRUBY PATTERN ON THE FLOOR OF THE RAIN
FOREST.]
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.
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 outgrow all others and send their roots down the flanks of the
rotting log and into the ground. 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 saprophytes—plants 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.
[Illustration: THE SHELF FUNGUS IS ONE OF THE NUMEROUS ATTRACTIVE
FUNGI.]
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....