176 Irrigation and Drainage 



The amount of water given to this crop was 8.245 inches, in 

 four applications, July 21, Aug. 3 and 10, and Sept. 3, 2.061 

 inches being applied each time. 



The difference between equal numbers of rows of cabbage 

 irrigated and not irrigated is shown in Fig. 29. Were the cabbage 

 grown for green fall and early winter feed for stock it will be seen 

 that the close setting gives a difference in favor of irrigation 



Fig. 29. Difference in yield between cabbage, irrigated and not irrigated. 



amounting to 7.35 tons per acre. This occurred, too, under con- 

 ditions in which the plots not irrigated received considerable 

 water from seepage from the heavy irrigation of a piece of 

 meadow. 



The same season that these experiments were made with cab- 

 bage, similar ones were conducted with mangold- wurzels and with 

 turnips. But while a good yield of beets was secured per acre, 

 namely, 15.7 tons, there was only 18 pounds difference, the six 

 rows of irrigated mangolds yielding 5,100 pounds and those not 

 irrigated 5,082 pounds. The turnips, on account of a blight, 

 did nothing under either treatment, and the same was true foi 

 rape. 



THE EFFECT OF SUPPLEMENTING THE RAINFALL WITH 

 IRRIGATION ON THE YIELD OF CORN 



During four consecutive years we have grown corn upon one 

 area, irrigating a part and reserving another part not irri- 

 gated, as a check. The soil of this plot is medium clay Ioam 



