4 BULLETIN 654, U. S. DEPARTMENT OF AGRICULTURE. 
acres in the largest-size group, and there is no indication that still 
larger farms would not continue to pa}- still larger labor incomes. 
Here, as elsewhere, the minimum farm unit should be large enough 
to afford the farm family at least a comfortable living, with some 
margin for savings. Whether it should be large enough to pay "rea- 
sonable wages" for the farmer's labor is a matter to be decided by the ( 
individual concerned. The personal ability of the operator and the 
means at his command are factors that must be considered. 
Small farms are more intensively farmed than large ones, but thei 
large farms give better returns for a given amount of labor. One! 
man manages eight times as many acres, five times as many live stock, 
and three times as much capital on the very large farms as on the 
very small farms; and this more than compensates for the greater re- 
turns per acre on the small farms. However, increasing receipts per 
acre pays on large farms, the farm income and labor income both 
rising as receipts per acre increase, even though the average area 
farmed decreases. 
Of a total of 627 farmers, 466 managed their farms so as to make 
them pay an average of 13 per cent on the investment in addition to 
the farm contribution to the family living, while 161 farmers were able 
to make their farms pay but 5.9 per cent on the investment, the labor 1 
of the farmer himself not being included in expenses in either case.! i 
This difference was due almost entirely to differences in gross receipts 
obtained by the two groups of farmers. 
It was found that gross receipts are influenced by the type of farm- 
ing, the amount of working capital per acre, the number of acres, I; 
farmed per man, the productivity of the land, and the quality of the 
live stock. All of these factors are largely within the control of the 
Arizona farmer. 
GENERAL DESCRIPTION OF LOCALITIES. 
SALT RIVER VALLEY. 
Salt River Valley is the largest of the three valleys studied. It ex- 
tends from the junction of the Verde River with Salt River to the 
junction of the Salt with the Gila River, a distance of about 50 miles.il 
Its average width is approximately 20 miles. It contains somewhat! 
over 200,000 acres of irrigated lands, about three-fifths of which are 
on the north side of the river. 
The soils, being of alluvial origin, are deep, and vary in texture % 
from light sands to heavy clays, or " adobe. " They are fully de-1 
scribed and mapped in a bulletin 1 issued by the Bureau of Soils of 
the United States Department of Agriculture. 
The climate may be classified as subtropical. There is a long, hot 
summer and a short, mild winter. The heat in summer is greatly] 
i A Soil Survey in Salt River Valley, Ariz. 
