14 



Journal of Agricultural Research 



Vol. XIII, No. I 



Table IV. — Water content before and after irrigation, the tnoisture equivalent and the 

 pore space of the soils of typical alfalfa farins in Sacramento Valley, California, 

 iQij-igi^. Averages for each foot of soil to a depth of 6 feet " 



[Results expressed in acre-inches per acre-foot of soil] 



CLAY-LOAM SOILS, I913-14 & 



Tract, location, and time of sampling. 



Num- 

 ber 

 of 

 bor- 

 ings 

 for 

 soil 

 sam- 

 ples. 



Water content. 



Mois- 

 ture 

 equiv- 

 alent 



in 

 acre- 

 inches 

 per 

 acre- 

 foot 

 of soil. 



Pore- 

 space 

 acre- 

 inches 

 per 

 acre- 

 foot 

 of soil. 



Depth of soil at which samples were taken. 



O'Hair, Orland: 



Before irrigation 



After irrigation 



Increase 



Geer, Los Molinos: 



Before irrigation 



After irrigation 



Increase 



Guile, Woodland: 



Before irrigation 



After irrigation 



Increase 



Jackson- Woodard, Woodland: 



Before irrigation 



After irrigation 



Increase 



Wright, Dixon:_ 



Before irrigation 



After irrigation 



Increase 



Averages: 



Before irrigation 



After irrigation 



Inciease 



2.66 



3-27 

 .61 



2.74 



3.20 



.46 



3-12 



3-31 



.19 



3-41 



3-72 



•31 



3^03 



3-34 



•31 



3-51 



3-44 

 — .07 



2.67 



3-21 



•54 



2. 72 



3.18 



.46 



3-25 

 3-46 



3-47 



3^70 



•23 



3.12 



3- 40 

 .28 





6.36 



S.78 



6. 42 



5-38 



CLAY SOILS, 1914 



Purdy, Willows: 



Before irrigation 



After irrigation 



Increase 



Tuttle, Willows: 



Before irrigation 



Aiter irrigation 



Increase 



Averages: 



Before irrigation . 

 After irrigation . . 

 Increase 



1.69 



3.06 

 I. 71 



2. 12 

 •13 



2.09 



2. 70 

 .61 



2.04 

 2.41 

 •37 



3- 16 



3-29 

 •13 



3-44 

 3-42 

 — . 02 



4-36 

 4.06 

 -•30 



3-92 

 3-79 

 -■13 



1- 



"■ See Table II for the number of times each of the above fields were irrigated, the average quantities of 

 •water applied, and the total amounts of water retained by the soil. 



b These data are presented graphically in figure 4. 



« The plan of sampling the upper 2 feet of the clay soils was in 1915 changed from one sample in the middle 

 of each foot-section to one in the middle of each 8-inch section, thus giving three samples in the upper 2 

 feet. The sixth foot was not sampled in 1915. These data are presented graphically in figures 5 and 6. 



