BULLETIN OF THE 
1 
No. 10 
Contribution from Office of Experiment Stations, A. C. True, Director. 
October 30, 1913. 
„ 
PROGRESS REPORT OF COOPERATIVE IRRIGATION 
EXPERIMENTS AT CALIFORNIA UNIVERSITY 
FARM, DAVIS, CAL., 1909-1912. 
By S. H. Beckett, 
Irrigation Engineer. 
INTRODUCTION. 
/ 
The experiments herein described were planned and carried out for 
the purpose of determining the water requirements of v&*iQus Stand- 
ard crops. For the purpose a tract of 25 acres on the University farm 
at Davis was set aside by the college of agriculture. The work was 
planned and carried on by the irrigation investigations of the Office 
of Experiment Stations, in cooperation with the department of en- 
gineering of the State of California, the California Experiment Sta- 
tion furnishing seed and a part of the labor in return for the crops. 
The University farm, comprising 779 acres, lies one-half mile west 
of the town of Davis. The soil, which is typical of that of a great 
portion of the Sacramento Valley, is classed as Yolo loam, described 
by the Bureau of Soils of this department, as follows : 
The surface soil of the Yolo loam consists of a dark-brown loam of light to 
rather heavy texture. The soil is usually free from gravel. Below a depth of 
24 inches the subsoil is generally made up of strata of silty loam or sandy loam. 
At greater depths this rests on clay loam or clay. . * * * 
Owing to the excellent drainage and comparatively open texture of this type 
it has proved to be well adapted to fruit, including peaches, almonds, prunes, 
and grapes. * * * While irrigation has not been in general use. it has 
been found to be beneficial to the tree and fruit where the lower strata of the 
soil lack the close texture and compactness necessary for the retention of mois- 
ture. It is one of the best general-purpose soils in the region and is adapted to 
a wide range of crops. 1 
The mean annual rainfall, although slightly below the average for 
the Sacramento Valley as a whole, amounts to 16.54 inches, the 
greater part of which comes in December, January, February, and 
March, while from May to October very little rain falls. A mean 
temperature of 77.9° F. is recorded for the month of July, the mean 
1 U. S. Dept. Agr., Bur. Soils, Field Operations, 1909, Eleventh fieport, pp. 1657, 1658. 
6137°— Bull. 10—13 1 
