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Cerco carpus (mountain mahogany), Crataegus (hawthorn), Rosa (rosebushes) , 
and Frunus (chckecherry) . 
7 . M ontane (collections made only in Colorado ) — 
Represented "by lodgepole pine ( Pinus murrayana ) , Engelmann spruce 
( P i c e a e nge lmanni ) , Colorado "blue spruce (R. pungens ) , and quaking aspen 
(PpjDulus tremuloides ) . Along streams are found willow ( Salix ) , birch (Be tula) , 
and honeysuckle ( Lonicera ) . In the openings are sedges ( Carex ) , sages 
( Artemisia ) , sandwort (Arer.a ria ) , lupines ( Lupinus ) , shrubby cingxuofoil 
( Dasiphora f ruticosa ) , locoweed ( Astragalus ) , larkspur ( Delphinium ) , paint- 
brush ( Pastill e ja) , and many others. 
8. Alpine meadows, above timber line — 
Characterized by timber-line effects on Engelmann spruce, causing them 
to grow along the ground, dwarf willows, and other plants, monkshood ( Aconitum ), 
bluebell (Me rt en si a) , sedges (Carcx), phlox, goldenrod ( S olidago ) , cowslip 
( Primula ) , gentian ( "D^ systephana ) , and many more. 
9 . Sagebrush, or northern desert shrub — 
All of Wyoming west of Laramie and Big Horn Mountains, except the 
mountain areas and all of the Great Basin region ir Utah. The plants are 
sages ( Artemisia tridentc r-a, A. nova, and A. rigid a") , salt sages ( Atriples 
corrugata , A. nuttallii , and allied species), matchweed ( Gutierrezia sarothrae ) , 
big and little rabbi thrush ( Chrysothamnus nauseosus and C. stenophyllis) , 
winter fat ( Eurotia lanata ) , and certain annuals, military grass ^ ( Bromus 
tectorum) , alfilaria ( Erodium cicutarium ), and other desert species. 
These natural vegetation areas overlap and the plants that dominate 
one area may be important throughout another. Most of the collections were 
made either in or close to cultivated crops. In some instances special efforts 
were made to collect in the native environments away from the influence of 
cultivation. 
The cropped area and pasture and hay grassland environments are varied 
because of differences of natural vegetation and climate. In the eastern and 
more humid portions of the survey territory, the fields are smaller and more 
cut up by fencerows and roadsides, and the bordering vegetation is much more 
rank and lush than in the drier, more arid western part. Therefore, a wheat 
field in eastern Montana furnishes a different environment than does a wheat 
field in Iowa, Wisconsin, or other States having greater rainfall. The grain 
fields in the more arid short-grass region are surrounded by large tracts of 
open range, and the populations there are influenced by the surrounding short- 
grass species of grasshoppers. The percentage of the total land area of the 
State in harvested crops is about 60 percent in Iowa and 4 percent in Montana. 
With the breaking up of the native vegetation into farms, many new plants have 
been introduced in the form of crops and weeds. 
