10 



FORAGE-CROP EXPERIMENTS AT SAN ANTONIO. 



ing the early part of the season. The cultivation of the sorghum in 

 4-foot rows conserved a large part of the rainfall for the use of the 

 crop, while the plats in 8-inch drills were dependent entirely upon 

 the season's rain, as there was very little moisture carried over from 

 1909 and the rain that did fall was lost very quickly by evaporation. 

 Up to about May 1 the spring of 1911 was unusually favorable, 

 the rains coming so frequently that considerable periods passed when 

 it was impossible to cultivate. Thus, before May 1 cultivation did 

 not affect the yields as much as it would otherwise have done and 

 the shortage of rain in June prevented a second cutting, enabling the 

 drilled plat to outyield the cultivated plat. When a series of years 

 is considered, it is safe to conclude that for unirrigated land planting 

 in rows, so that cultivation is possible, will increase the yields enough 

 to justify this method of planting. (PI. I, fig. 2, and PI. II, fig. 1.) 

 The effect of the two systems of cultivation on the succeeding crops 

 is also important. In the rotation experiments in 1911 there was a 

 slight difference in the yield of corn and a very noticeable difference 

 in the cotton yield in favor of the land on which sorghum had been 

 grown in cultivated rows the previous year. Under irrigation the 

 advantage was still with the cultivated rows. In rows 3 feet apart 

 the yield was 14.41 tons per aero, while in 8-inch drills the yield was 

 12.6 tons. The difference in yield is, however, comparatively slight; 

 and when one considers the expense of cultivating the rows, the 

 quality of the forage, and the greater ease of handling the broad- 

 casted sorghum it is doubtful whether it is profitable under irrigation 

 to plant in rows and cultivate. 



Width of rows. — A test was made in one-ten th-acre plats of sorghum 

 planted in rows, 2, 3, and 4 feet apart. Table V shows the yields 

 from these plats. 



Table V. — Yields of Sumac son/hum planted in rows 2, ■ >. and 4 feet apart. 



The plats of 1910 were planted in a field summer-fallowed in 1909, 

 and consequently the yields are not comparable with those given in 

 Table IY. The land on which the experiment was conducted in 1911 

 was cropped the previous year. In both years the quality of the 

 forage was best on the plat with the rows 2 feet apart, with the forage 

 from the rows 3 feet feet apart second in quality. While the differ- 

 ences are not great, yet the quality of the forage was so much better 



rr-ir ififii 



