IO HORTICULTURE BY IRRIGATION. 



This is undoubtedly true, and yet it offers no solution of the problem 

 of what the actual duty of water is. The amount of water uted, and what 

 is really needed, are two very different things. The systems or facilities 

 employed for distribution cut an important figure. Instances are given 

 in California where a flow of one cubic foot per second has supplied 9,000 

 acres, while in Colorado the average duty is estimated at 50 acres for the 

 same flow. 



A Massachusetts man estimates that 108 tons of water are needed per 

 acre, every five days, in a dry period for irrigating the garden lands of 

 that section, and a fruit grower of Wisconsin, who waters his fruits by 

 means of wind-mill and tank, reports that it takes 30,000 gallons to a 

 watering to satisfy his acre of strawberry plants. Under a system of sub- 

 irrigation, the State Engineer of California reported that he saw three 

 acres of young trees thoroughly irrigated, in half an hour, with about four 

 hundred cubic feet of water, or less that 3,000 gallons. The "duty " then, 

 under the flooding process, is vastly less than under the furrow system, 

 and by an improved system of sub-irrigation, it is as a hundred to one in 

 favor of the latter. These are suggestive figures, and some day will be 

 looked into when the waters from our streams become too valuable to 

 waste. It will be a forcible reminder of the old adage that "economy is 

 wealth." Still, even under frugal management, the demands of vegetable 

 life are comparatively large.* 



Few people realize the amount of moisture utilized and required by 

 growing plants and vegetation. Dr. Gilbert has stated that the amount 

 of water given off by plants during growth might be approximately esti- 

 timated as equal to a depth of three inches of rain for every ton of dry 

 substance grown. Another eminent authority found that most plants 

 exhaled during the four or five months of their growth, more than two 

 hundred times their dry weight of water, drawn up from the soil in which 

 they grew. 



Prof. Buirell, of the University of Illinois, says, in a recent report, 

 that "the water requirements of a tree, in full leaf, in warm, sunshiny 

 weather, are astonishingly great. A good sized apple tree, having 25,000 

 square feet of evaporating surface by no means a large estimate will 

 give off 31,250 ounces of water per day. This is substantially 250 gallons ; 



*NOTE. The experiments now being made at the Colorado State Agricultural 

 College, to determine the duty of water on various crops, will be watched with 

 interest. 



