276 Kansas State Board of Agriculture. 



IRRIGATION OF ALFALFA. 



By H. B. WALKER, State Irrigation Engineer, Kansas State Agricultural College. 

 ESSENTIALS FOR ALFALFA. 



Experience in the growing of alfalfa indicates that this valuable 

 legume thrives best in a rich, deep, well-drained soil, where there is an 

 abundance of sunshine, comparatively high summer temperatures, and a 

 well-regulated moisture supply. Where irrigation can be practiced the 

 western part of Kansas affords these essential conditions. The deep, 

 loamy soils of this region have unquestioned fertility, sunshine is abund- 

 ant, and the summer temperatures average rather high. Quite naturally, 

 however, where sunshine is so abundant moisture by natural precipita- 

 tion is often lacking. This is true of a considerable area in Kansas. Much 

 of our otherwise naturally best-adapted land for the culture of alfalfa 

 must be artificially supplied with moisture to produce paying crops of 

 this legume. It is only natural that our principal irrigated crop should 

 be alfalfa. 



KANSAS IRRIGATION. 



Irrigation in Kansas has never been extensively practiced, due largely 

 to the fact that our watercourses have never furnished an ample water 

 supply for gravity irrigation systems. Within the past ten years, how- 

 ever, very rapid and satisfactory progress has been made in pumping 

 from wells for irrigation. The development of the immense underground 

 water supplies which are known to underlie such a great part of this 

 territory is destined to be an important factor in western Kansas alfalfa 

 production. While it is not probable that extensive areas of this under- 

 flow district will be developed in the near future, the experiences of the 

 practical irrigation farmers so far indicate that all the desirable alfalfa 

 land in the shallow-water regions can unquestionably be economically 

 developed, and encouraging results obtained in the deep-well districts 

 give promise of the development of comparatively large areas of the 

 uplands. 



REQUIREMENTS FOR SATISFACTORY IRRIGATION. 



A very desirable and essential condition for satisfactory and success- 

 ful irrigation is a smooth surface with a uniform slope. Kansas land 

 which is subject to irrigation is usually fairly smooth, but even under 

 the most favorable conditions it is hardly probable that a single field can 

 be found which will not require some leveling before satisfactory irriga- 

 tion can be carried out. A rough, uneven surface permits the water to 

 collect in pools at some points, thereby resulting in injury to the crops and 

 the wasteful use of the water ; in other places too little water will reach the 

 land, and the crops will accordingly suffer from lack of moisture. Where 

 both water and land are cheap uneven surfaces might be irrigated without 

 complete failure, but the Kansas farmer must fully appreciate the value 

 of the correct spreading of the water at the outset; otherwise he is sure 

 to meet with failure. Generally speaking, pumped water is more ex- 

 pensive than water taken from a canal. The pumped irrigation water 



