44 



THE IRRIGATION AGE. 



and properly prepared at the outset. Too much em- 

 phasis can hardly be placed upon the preparation of 

 the land for the irrigation of alfalfa. Water cannot 

 be made to run up hill, and it is absolutely impera- 

 tive if good success is to obtained with alfalfa that 

 all knolls and hollows be so levelled down at the 

 outset before the alfalfa is planted that the water can 

 be made to run uninterruptedly from one head ditch 

 to the next one below it. There is much more rea- 

 son for careful levelling of the ground before plant- 

 ing alfalfa, pasture or other permanent crops, than 

 there is with grain, for the same trouble will be 

 experienced with every little hill and hollow every 

 time the alfalfa is irrigated every year, while where 

 grain is planted there is an additional opportunity of 

 doing more levelling on the land each spring. 



When to Irrigate Alfalfa 



Careful experiments have been made during the 

 past few years to determine at what stage of growth 

 alfalfa needs irrigation, and it has been found that it 

 needs a practically constant uniform supply of 

 moisture throughout the season. 



This condition can only be brought about where 

 irrigation is possible, yet owing to the variation in 

 the precipitation in this section, no hard and fast 

 rule can be laid down, either as to the number of 

 irrigations required or the stage of growth at which 

 they should be applied. Much will depend upon the 

 type of soil and the amount of rainfall received dur- 

 ing the season. Every irrigator should learn to 

 study the needs of his own particular soil and crops, 

 and then apply his irrigation water at such times 

 and in such amounts as will maintain the necessary 

 constant uniform moisture supply in the soil. 

 Alfalfa should never be allowed to become too dry, 

 and above all, water should never be allowed to 

 stand on it during irrigation for over twelve hours 

 at a time. Neither should it go into winter quarters 

 in a very wet, muddy condition, as winter killing 

 may result. During normal years in this section 

 alfalfa will probably require from two to three irri- 

 gations during the season. 



Amount of Water Required 



Alfalfa is a gross feeder, and grows luxuriantly 

 throughout the season, there being a very large 

 amount of leaf surface exposed to the sun and wind, 

 from which an unusual amount of transpiration 

 takes place. Alfalfa, therefore, requires corfsider- 

 ably more water than almost any other crop we can 

 produce, all other conditions being uniform. A long 

 series of careful, exhaustive experiments were con- 

 ducted under my supervision by the United States 

 Government for this purpose, and demonstrated that 

 where all other conditions are similar, alfalfa re- 

 quires twice as much irrigation water during a sea- 

 son as grain. Where grain does best with one 

 acre-foot per acre, alfalfa requires two acre-feet, and 

 where grain requires one and one-half acre-feet, 

 alfalfa requires three feet, and has a tendency to 

 produce the most crop where the most water is sup- 

 plied, though care must be used not to over-saturate 

 or waterlog the soil, for alfalfa will not stand "wet 

 feet." 



Time to Cut 



Alfalfa is pre-eminently adapted as a hay crop, 

 for no other forage recuperates so quickly after cut- 



ting. Parts of southern Arizona and the Imperial 

 Valley, California, cut alfalfa as often as nine times 

 a year. In order to secure the largest possible crop 

 of the highest possible feeding value, however, al- 

 falfa must be cut at the proper stage. This is at the 

 time that the little basal shoots or the sprouts of the 

 next crop start, which is uaually when the crop is 

 about one-tenth in bloom. If the crop is left until 

 one-half or in full bloom these basal shoots will have 

 grown so long that the mower will clip their tops, 

 thus retarding the start of the second crop, while if 

 it is cut at the proper time just as their basal shoots 

 start up around the crowns near the ground, the 

 next crop will come on and begin growth immedi- 

 ately, provided the necessary amount of moisture is 

 available in the soil at the time. 



General Treatment, First and Succeeding Years 



There is insufficient time and space at my dis- 

 posal to make a general discussion of alfalfa in all 

 its phases. These other phases will be taken up by 

 other papers. I wish, however, to dwell slightly on 

 the general treatment of alfalfa. After planting 

 alfalfa, there is nothing to be done with it until it is 

 from six to ten inches high, except to see that it has 

 the proper supply of moisture. At from six to ten 

 inches in height, no matter whether the field is 

 weedy or not, it should be clipped in order to 

 strengthen the crowns and thicken up the growth. 

 If the season has been favorable enough and the 

 initial planting early, there may yet be time to se- 

 cure one crop during that season, though in the 

 majority of cases even in much milder climates no 

 crop at all is expected the first year. Mr. H. Lausen 

 of Carseland during the past season has secured 

 about as large a yield from alfalfa for the first sea- 

 son as I have ever seen, even in the mild climates 

 of Colorado, Utah or Idaho. Mr. Lausen planted 

 two acres during the latter part of May, 1915, and 

 in August harvested one and one-third tons of cured 

 hay per acre from the plot. This I consider to be 

 phenomenal. If the initial planting of alfalfa has 

 been done so late in 'the season that clipping when 

 it has reached from six to ten inches in height will 

 force it to go into winter quarters with less than 

 four inches of growth, I would not clip it the first 

 year at all, for alfalfa, in order to be able to with- 

 stand the winter in the best possible shape, should 

 have some amount of growth at the time the ground 

 freezes up. This holds particularly true for the first 

 season. In the subsequent years alfalfa requires no 

 unusual treatment, except that care must be used 

 that it has a proper supply of moisture, that water 

 does not stand upon it, and that the crops are cut 

 and cured properly. Discing and loosening up of 

 the surface each spring, after about the third year, 

 has been found to be beneficial in many localities, 

 particularly if weeds or grass have a tendency to 

 creep in. Under these conditions discing even' 

 spring will be advised here. 



Hardiness and Vitality of Alfalfa 



There is no doubt in regard to the hardiness and 

 long life of the alfalfa plant in this section. If 

 planted on the proper class of well-drained soil it 

 will positively do as well here as in any similar 

 climate on earth. It has been my pleasure during 



