22 SNAKE RIVEK PLAINS OF IDAHO. [bull. 199. 
The reader will perhaps think that I have devoted too much space 
in attempting to record some of the leading features of the climate 
and weather of this region, but it is to be remembered that there is an 
intimate connection between the surface features of a region and the 
climatic conditions to which it is exposed. Not only is the nature and 
origin of the soil of the Snake River Plains to be looked for in part at 
least in the work of the winds, but the canyon walls, the widely 
spreading alluvial fans, and the details in the bordering mountains 
would not be what we now find if humid instead of arid conditions had 
long prevailed. Still more quickly responsive to climatic conditions 
is the vegetation which soils are permitted to produce. 
VEGETATION. 
The ever-present and characteristic plant of the Snake River Plains 
is the sagebrush {Artemisia tridentatci), which grows abundantly and 
we might say luxuriantly in the dry soil, from the bottom of the 
Snake River Canyon up to an elevation of some 2,000 or 3,000 or more 
feet on the mountains bordering the plains. It covers the broad arid 
valleys almost completely and is seldom lacking over any extensive 
area, except where fires have recently occurred or cultivated fields 
supplanted it. On the plains in summer fire sometimes sweeps 
through the sagebrush in much the same manner that it does over the 
prairies, and " burns" are produced. The "sage," in the localities 
most favorable to its growth, attains a height of about 10 feet, but 
usually is not over 3 feet high, the clump of bushes being commonly 
6 to 8 feet apart. One can ride or walk ov r er the sagebrush plains 
with but little difficulty. The light grayish-green leaves of this 
ubiquitous plant give color, or perhaps more properly lack of color, 
to the plains and enhance their monotony. Although the Snake 
River Plains are frequently termed a desert, the name is true only in 
the sense that they are practically without water. There is compara- 
tively little of the surface that is entirety destitute of plant life. In 
fact the flora is found to be abundant and varied, if one examines it 
closely. There are many lovely plants that blossom in early spring, 
filling the air with fragrance, and in summer and fall the yellow of 
sunflowers and of the still more plentiful "rabbit brush" (Bigdovia 
graveolens), a relative of the goldenrod, frequently give broad dashes of 
brilliant color. Beneath the sagebrush in a state of nature nutritious 
bunch grass grows abundantly and still furnishes pasturage where 
sheep have not ravished the land. Where the plains are broadest, 
that is to the north of the Oregon Short Line Railroad and especially 
in the vicinity of the three steptoes, Big, Middle, and East buttes, 
much of the land is without sagebrush and in the condition of a rolling 
prairie which supplies excellent winter pasturage. 
One of the surprises met with during the reconnaissance which fur- 
