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.

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 floor—most of them

flowering plants such as pinedrops, Indian-pipe, and coralroot.

[Illustration: RED ALDER IS THE FIRST TREE TO GROW AT THE EDGE OF

THE CHANGING COURSES OF THE RAIN FOREST RIVERS.]

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.

[Illustration: THE CANADIAN AND HUDSONIAN LIFE ZONES ARE REPRESENTED

IN THE RESPECTIVELY HIGHER FOREST BELTS THAT LIE ABOVE LUSH RAIN

FORESTS.]

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.

[Illustration: MEADOWS AND CLUSTERS OF TREES OF THE HUDSONIAN ZONE.]

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.

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 lomatium—their 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.

[Illustration: ALPINE FIR GROWS NEAR TIMBERLINE.]

[Illustration: WESTERN REDCEDAR BARK HAS FAIRLY REGULAR NARROW

GROOVES AND RIDGES.]

[Illustration: NEXT TO THE SEQUOIAS OF CALIFORNIA, DOUGLAS-FIR IS

THE GREATEST TREE IN THE FORESTS OF THE WESTERN HEMISPHERE.]

[Illustration: WESTERN REDCEDAR. CONES ARE ABUNDANT ON SOME TREES.]

Olympic National Park, Washington · 第 9 / 37 题