6. Earth’s Green Mantle
WATER, SOIL, and the earth’s green mantle of plants make up the world that s upports
the animal life of the earth.
Although modern ma n s eldom re me mbe rs the fact, he could not exis t without the plants that
harnes s the s un’s energy and manufacture the bas ic foods tuffs he de pends upon f or life. Our
attitude toward plants is a singularly narrow one. If we see any immediate utility in a plant we
foster it. If for any reason we find its presence undesirable or merely a matter of indiffere nce,
we ma y condemn it to des truction f orthwith. Bes ides the various plants that are pois onous to
man or his lives tock, or crowd out food plants , many are marke d for des truction merely
becaus e, according to our narrow view, the y happe n to be in the wrong place at the wro ng
time. Ma ny others are des troyed me rely becaus e they happen to be associates of the
unwanted plants.
The earth’s vegetation is part of a web of life in which there are intimate and essential relations
betwee n plants and the ea rth, betwee n plants and othe r plants , between plants and ani mals.
Sometimes we have no choice but to dis turb thes e relations hips , but we s hould do s o
thoughtfully, with full awareness that what we do may have cons equences remote in time and
place. But no s uch humility ma rks the booming ‘weed killer’ bus ines s of the pres ent day, in
which soaring sales and expanding us es mark the produc tion of plant-killing chemicals. O ne of
the mos t tragic examples of our unthinking bludgeoning of the lands cape is to be s een in the
s agebrus h lands of the Wes t, whe re a vas t campaign is on to des troy the s age and to s ubs titute
grass lands. If ever an enterpris e needed to be illuminated with a s ens e of the his tory and
meaning of the lands cape, it is this. For here the natural lands cape is eloquent of the interplay
of forces that have created it. I t is s pread before us like the pages of an open book in which we
can read why the land is what it is , and why we s hould pres erve its integrity. But the pages lie
unread.
The land of the s age is the land of the high wes tern plains and the lower s lopes of the
mountains that ris e above them, a land born of the great uplift of the Rocky Mountain s ys tem
many millions of years ago. It is a place of harsh extremes of climate: of long winters when
blizzards drive down from the mountains and s now lies deep on the plains , of s ummers whos e
heat is relieved by only scanty rains , with drought biting deep into the s oil, and drying winds
stealing moisture from leaf and stem. As the lands cape evolved, there mus t have bee n a long
period of trial and error in which plants attempted the colonization of this high and winds wept
land. One after another mus t have failed. At las t one group of plants evolved which combined
all the qualities needed to s urvive. The s age—low-growing and s hrubby—could hold its place
on the mountain slopes and on the plains, and within its small gray leaves it could hold
mois ture enough to defy the thieving winds. It was no accident, but rathe r the res ult of long
ages of experimentation by nature, that the great plains of the Wes t became the land of the
s ag e.
Along with the plants, animal life, too, was evolving in harmony with the searching
requi reme nts of the land. I n time there were two as perfectly adjus ted to their habitat as the
sage. One was a mammal, the fleet and g raceful pronghorn antelope. The other was a bird, the
sage grouse—the ‘cock of the plains’ of Lewis and Clark. The sage and the grouse seem made