534. REPORT OF THE COMMISSIONER OF AGRICULTURE. 
The extent of the forest area is about 580 square miles. 
The lines of drainage are northwest and west, mostly subterraneous, and empty into 
the Gila River. 
The principal rainfalls oceur in July and August; the amount of rainfall durin 
those months in 1876 was 8.55 inches, and in 1877 &.00 inches. The total amount o 
rainfall during the past two years was 26.55 inches, Very light and occasional falls 
of snow occur during the winter months. 3 ; 
FORT YUMA. 
Latitude 32° 43’ 32’; longitude, 114° 36’ 08’. The post commander reports that the 
post is on three sides encompassed by the river bottom, which at this point averages 
about five miles in width. These bottom lands give the forest area of this vicinity. 
They are densely covered with mesquite and an undergrowth of arrow-weed. Cotton- 
wood, willows, and mesquite grow on the banks of the river and lagunas. 
The Colorado River and its tributary, the Gila River, form the line of draimage of 
the surrounding country. ; 
The average annual rainfall at Fort Yuma for the last five years has been 4 inches, 
as ascertained by actual measurement. This, with the annual overflow of the Colo- 
ete River, gives sufficient moisture for a dense growth of timber on the bottom 
ands. 
None of the trees mentioned attain a height of over 30 feet. The cottonwood and 
willows are stripped of their bark and used for building fences and as a foundation 
for mud roofs. 
Of the mesquite tree (a tree of the Mimosa family, with thorns and small pinnated 
leaves), two varieties are found in the vicinity of Fort Yuma, the long-pod mesquite 
(Algarobia glandulosa) and the screw-pod mesquite ; the former bearing a pod from 4 
to 6 inches in length, and the latter, as the name implies, bearing a pod in the shape 
of a screw, from two to three inches long. These pods contain from six to twelve 
beans, inclosed in a pulpy substance. They have a flavor not unlike the tamarind, 
contain a considerable amount of saccharine matter, and are wholesome and nutri- 
tious. Both varieties are used by the Yuma Indians for food. They gather the 
beans in large quantities when ripe, and reduce them to flour by grinding between 
two stones. Large qnantities are also sold to the whites, and used as food for horses 
and cattle. The mesquite tree also furnishes a kind of gum, which has the same proper- 
ties as gum ‘arabic, and can be used for all purposes to which the latter is applied. 
Tt flows from the bark of the tree during the summer months, and hardens on expo- 
sure to the air. 
On the mesas, which border on the river-bottoms, the vegetation is very scant, and 
consists of a few stunted mesquite trees and several varieties of cactus. 
CAMP M DOWELL. 
Latitude, 33° 46’; longitude, 111940’. Mesquite wood and palo verde abound in plen- 
tiful quantities on the plains surrounding this pest. Cottonwood is plentiful in the 
Salt River bottom, and from these sources the post is supplied. As the mesquite and 
palo verde are of short growth, and the cottonwood found only in the bottoms, it can- 
not be said that there is anything like a forest in this vicinity. The mesquite and 
palo verde are a very hard wood, the former of a dark color, the latter light. Cotton- 
wood is soft and light. 
The elevation of the post, taken barometrically, is 1,800 feet above sea-level. The 
rainfall at the post during the year 1876 was 2.20 inches. 
FORT WHIPPLE. 
Latitude, 34° 33’; longitude, 112° 30’. The commanding officer reports that the 
forestry in the vicinity of this post consists principally of pine (pitch and spruce), 
juniper, cedar, scrub oak, and some manzanita. <A belt of timber, principally pine, 
called the Bradshaw timber-belt, extends about forty miles south and twelve miles 
west, and is about twenty miles in width. ‘To the east the timber (pine and serub- 
oak) extends about four miles. To the north there is but little timber. The pine 
timber is rapidly disappearing, supplying the saw-mills in this vicinity, and for fuel. 
The arable land is not very extensive; cultivation is confined to valleys that retain 
moisture, and the rainfall is principally relied upon for success. In very dry seasons 
the crop is anentire failure. An instance of this kind occurred last year, when scarcely 
grain enough was raised by the farmers to supply their own wants. The largest arable 
tract (about one thousand acres) is on Willow Creek, and three or four thousand acres 
will cover the total arable land. All the farmers écpend on the natural water-supply, 
