COLOR^IDO 
This is the "fifth year in which collections have h^en, made in 
Colorado. There were 10,135 specimens collected in 9 environments in 
the cropland on the plains and 8 habitats ••classified ac cor, ding, to . . 
elevation above sea level. These elevations are .listed ag ”bel6w 5,', 000 ; 
feet," » 5, 000 to 7,000 feet," "7,000 to 9, 000. feet," "9 ,odb 'to;iI,^ 
feet," and "above 11,000 feet," The hipest elevations were th6 st^ 
of Pikes Peak and Mount Evans, with altitudes of over I4,00d feet. ‘ ^ 
Altogether, 73 species were represented in the collections for the entire 
State. 
Several outstanding facts are brou^t out in the collections for 
this State. In the first place, it was done systematically and the results 
show a perfect distribution of species as wotild be esgjected according to 
habitats found in the cropped areas of the plains. As .an example, 
Melanoplus mexicanus was dominant in the small grain, but far more so in 
the diy-land grain than in the irrigated crop. It was, also the mos.t 
numerous in sor^ums and idle land and was about equal with M. bivitta-fos 
in beans. Melanoplus femu3>-rubrum was the dominant species in alfalfa 
and along field margins, which is to be expected. In the corn M. differen- 
tial is was dominant, with M. bivittatus second and. M. femu3> - rubrum third, 
the three toother forming 94 percent of the. population. M. mexicanus. 
was fourth, forming only 2 percent. Between the dry-land and irrigated 
small grain, neither M. bivittatus , M. differential is , nor M. femur-rubrum 
appeared among the first five most important species in the dry land but 
in the irrigated section, they were second, third, .aa<i fif.th, respectively. 
These three species were also the first three most important species in. 
the field margins in the order just name d^ • Other, --than the dry-land grain 
and i(^e land, the' crops listed here,, including the margins, are largetly 
under irrigation. Therefore, the segregation of the .records on the b^sis 
of diy^l^d and irri'^ted land definitely divides .this ^as^opper in- 
festatiohs into almost a pure M. mexicanus. infestation for the former and 
a mixture of M. bivi-^tatiis , M. differentialis , M. femur-rubrum , and 
M. mexicanus for the latter. 
In the classification according to elevation above sea level, it 
may be noted that no Oamnula pellucida occured below 5,000 feet, and 
reached its greatest importance on the range land between 7,000 and 9,000 
feet, where it was the dominant species. It was also second in 
numbers in the alfalfa and small grain in this range of altitude and on 
range land between 9,000 and 11,000 feet. This species did not appear in 
any numbers at lower altitudes of the plains, woodland, or prairie, except 
in the more northern latitudes of the northern parts of Michigan, 
Wisconsin, Minnesota, and North Dakota. It is confined largely to the 
mountain and low mountain areas of the west. 
One of the most enli^tening facts is that Melanoplus mexicanus 
was by far the dominant species collected above 11,000 feet elevation, 
forming 62 percent of the 531 specimens collected at these altitudes. 
Some of these collections were made on the summits of Mount Evans and 
Pikes Peak — above 14,000 feet — and mexicanus was the dominant species. 
