The Florence tribune., 1900-06-09
IRRIGATION INVESTIGATION.
What is the Minimum Flow Necessary For
 Crop Production?


 Crop Production?
 The Department of Agriculture has in press an interesting bulletin pre- pared by Prof. B. c. Buffum, showing the results of his irrigation experi- ments for the past nine years at the Laramie, Wyoming, Experiment Sta tion.
 Professor Buffum states that the time has now arrived when many irrigated districts have so far devel- oped that scarcity of water is keenly felt, and the good of the community demands that there shall be no un- necessary waste of the limited supply. The knowledge lacking il irrigation, and which must in some way be cb- tained before our water supply will be either wisely or correctly used, is how much water is required to secure the best results, and when and by what means it can be most economically and efficiently applied.
 HOW MUCH WATER?
 Some of the experiments have been made with view to determining the effect of the use of greater or less quantity of water npon the crop return of given area. Professor Buffum presents tables showing the crop returns from various plants on which different quantities of water were used, but they are not conclusive and more experiments are needed. In general, however, the tables show larger yields where the larger quanti- ties of water were used, but the in- creased yields are not in proportion to the increased quantities of water used. The varying conditions affecting the quantity of water needed by crops are fully discussed in the bulletin. Most plants cultivated in the arid west were introduced from more humid regions, and are not economical in their water requirements. Selections of drought-resisting varieties may make possible great extension of the present irrigated area. Methods, too, of cultivation and irrigation have much to do with the quantity of water used. Flooding as Il rule requires more water than irrigating in furrows, and it has been observed that grass and grain, which are usually irrigated by flooding, produce more thrifty growth on ditch banks and higher ridges and knolls where the roots are supplied from beneath rather than from the surface. This fact has led in some localities to the adoption of the rill system with such crops as cover all tine land.
 STORAGE. RESERVOIRS NEEDED.
 The Laramie river is a type of many of the western rivers whose waters are used for irrigation. Professor Buffum's s tables and diagrams show that the river furnishes the greatest supply of water in May and the early part of June, and that all crops except native hay require the most water later in the season-the latter half of June and the first half of July. This means that irrigated farming along the | Laramie River must be limited to na- tive hay and the small area of other crops which can be irrigated with the summer flow of the river, unless the spring floods are stored for the use of those crops requiring later water. h Wyoming this is not so great hard ship as a like condition would be ir some other States. The fact that the greater part of the land in the state is beyond the reach of water makes stock raising the leading industry of tht state, and the great need of that in dustry is winter feed for the stocl which runs. on the open range during the summer months. But native hay is a light crop, even when irrigated and storage reservoirs would make i possible to cultivate an increase O area of other forage crops which yielt much more heavily than native hay. l Professor Buffum emphasizes thu fact which is brought out by almos every recent writer on irrigation, tha the present system of giving irriga tors title to the use of g conbinuou flow of stream of given size is no necessary and is moreover wasteful He shows that some system of rota tion by which the owner of 70 acre can have the use of a larger head tha l second-foot for short periods durin the season will more nearly correspon , with his needs and result in grea saving of water.
 The bulletin can be obtined by apply ing to the Secretary of Agriculture.
 A Great Final County Mine.
 The Engineering & Mining Journi published an interesting article o