TIME OF IRRIGATION 177 



ing the earlier periods of growth. Water stored in the 

 soil at the time of planting is invariably more valuable, 

 unit for unit, than water applied directly at the time of, 

 or immediately after planting. 



Fall irrigation may be applied to bare lands at any 

 time after harvest. The common practice is to apply the 

 water as soon as may be convenient after harvest without 

 previous plowing, and to allow the soil to remain unplowed 

 until the following spring. Another practice is to plow 

 soon after harvest and then to apply water. When the 

 soil "washes" easily, this latter practice is not always 

 successful; moreover, plowed land is irrigated with diffi- 

 culty. The structure of some soils is easily injured by 

 the work of making the water cover the plowed land, thus 

 affecting the crop of the following year. On orchards, fall 

 irrigation should not be applied too early. The soil 

 should be allowed to become dry in the early fall, so that 

 the trees may ripen their wood for the winter's rest. 

 Then fall irrigation may be applied in safety. If water is 

 applied to trees before growth has ceased, a late new 

 growth is started, which usually results in winter-killing. 

 Naturally, this applies only to deciduous trees. Citrus 

 trees are irrigated during the whole year, if necessary. 



Generally, when fall irrigation is applied late enough 

 it results only in good. Lands are not ordinarily culti- 

 vated after fall irrigations, because, over the larger part 

 of the irrigated territory, the fall rains usually leave the 

 top soil in a condition to be puddled if subjected to tillage. 

 However, a soil that has been fall-irrigated should be 

 carefully cultivated in the spring, just as soon as the top 

 soil is in the proper condition. It is never wise to use 

 tillage implements on soils that are too wet. Early spring 

 cultivation always means cultivation performed on a 

 L 



