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Irrigation of Grain

Walter Wesley McLaughlin

出版	U.S. Department of Agriculture, 1917
URL	http://books.google.com.hk/books?id=9HxaDY2z_tYC&hl=&source=gbs_api
EBook	FULL_PUBLIC_DOMAIN

註釋

"Methods of irrigating grain crops are restricted somewhat because of the fact that such crops cover the entire surface of the plot on which they are grown. Objections to the flooding method, based on loss of water by evaporation, have less weight the irrigation of grain than of other crops, grain fields seldom being irrigated after the seed is planted until the grain is high enough to protect the soil from sun and wind. Grain usually is the first crop grown on irrigated farms. For such farms flooding usually is better than other methods, since the preparation of the land for it is easier than for the other methods. Flooding from field ditches is the usual method of handling water in irrigating grain, but the border basin methods are also adapted to such crops. These methods are described in detail in this bulletin, which also discusses the proper time to irrigate, the quantity of water required, and the cost of growing grain under irrigation."--Page 2