8 
BULLETIN 1001, U. S. DEPARTMENT OE AGRICULTURE. 
irrigation water may be had. It is believed that much of the great 
plains region in eastern Montana and Wyoming, shown here as domi- 
nantly dry-farming land, will ultimately prove to be arid grazing 
land. 
Definite data as to the area of each class of land to be found in the 
western United States are not available, but there are estimates and 
in some cases exact figures from which an .approximation may be 
reached. 8 Using the more reliable of these figures and assuming (1) 
that the humid crop lands west of the Sierras (outside the National 
Forests) amount to as much as 20 millions of acres (which is cer- 
tainly ample) and (2) that there is at least as much arid grazing land 
in these 11 States as there is semiarid crop land (which is certainly 
an estimate in favor of the dry-farming land), the following results 
are obtained: 
Classification of land in the 11 Western States. 
Class of land. 
Acres 
Percent. 
Humid cron land 20, 000, 000 
Irrigable crop land 41, 000, 000 
Semiarid crop land j 260, 000, 000 
Arid grazing land j 260,000,000 
2.67 
5.47 
34.71 
34.71 
Class of land. 
Forest and woodland . 
Desert land 
Acres. Per cent. 
128, 000, 000 
40,000,000 
Total 749,000,000 
17.09 
5.35 
100.00 
s Below are presented the data relative to the various classes of lands in the 11 Western States, showing 
approximate area of each kind, in nearest whole number of millions of acres. 
Total 
land 
area. ' 
Area of 
national 
forests. 1 
Afea ti°g 5 inol° fil ~ ArGa for which ™ ter is mailable. 
States. 
Desert 
area. 2 
Fortier.s 
As shown 
by United Reported 
Newell.* ! S \ ates b ^ C / n " 
c c ! reclama- sus for 
tionproj- 1910. 6 
1 ects, 1918. 5 
Total area 
in all 
projects, 
Census 
1910.' 
Arizona 
73 
100 
66 
54 
93 
■ 70 
78 
61 
53 
43 
62 
11 
19 
13 
18 
16 
5 
8 
13 
7 
10 
8 
10 
1 
2 0. 25 0. 39 
0.94 
California 
Colorado 
20 
10 
3 
6 
17 
8 
5 
11 
2 
4 
3 
4 
3 
9 
.05 3.62 
. 14 3. 99 
. 55 2. 39 
.16 2.21 
.07 .84 
.12 .64 
. 07 .-83 
5.94 
5.92 
Idaho 
3.59 
3.52 
Nevada 
10 
2 
2 
3 
2 
1 
1.23 
New Mexico 
1.10 
2.53 
Utah 
.05 
.14 
.13 
1.25 
.47 
1.64 
1.95 
Washington 
Wyoming 
.82 
6 
2.22 
Total 
749 128 
40 41 
68 | 1.73 19.33 
31.11 
i United States Forester's Annual Report for June 30, 1919. This includes most of the forest and wood- 
land area. State and private holdings are not included in these figures; they amount to several millions 
of acres. 
a Rough estimate, based mainly upon the area receiving less than 5 inches average annual rainfall. The 
area is certainly more than 25 and less than 50 millions of acres in extent. 
* Fortier, Samuel, et al. National Conservation Commission's Report. Senate Doc. 676, 60th Congress, 
2d session, 1909. Vol. 2, p. 67. 
* Newell, F.H. Irrigation, 1906. These figures assume complete conservation and use of all water 
resources of each State. 
* Annual Report Reclamation Service for 191S. Figures show amount of water available for irrigation 
under United States reclamation projects, not all of which was used. 
6 Statistical Abstract, 13th Census Report. Total area for which water was available in 1910. These 
figures have doubtless been increased somewhat in the last decade, but the new data are not yet available. 
7 Same. Total area included in projects of all kinds in these States in 1910. In addition, there was in 
Kansas, Nebraska, North Dakota, Oklahoma, South Dakota, and Texas water for 1.06 millions of acres 
and 1.84 millions of acres of land in projects already in operation. 
