THE IKRIGATION AGE. 



method is used, irrigation as soon after sowing as pos- 

 sible is necessary to cause germination of the seed. If 

 sown in moist soil and covered deeply with an ordinary 

 harrow or with a disk harrow it will usually germinate 

 well and make a good stand without irrigation follow- 

 ing the sowing. The results from the two methods of 

 putting in grain are consequently quite different. Irri- 

 gating the dry soil after sowing the grain causes it to 

 bake and the surface to remain in a hard condition, 

 unless a harrow is run over the field before the grain 

 is too large to be injured, and in any case the condition 

 of the soil is such that another irrigation will be 

 needed before that sown in moist soil will show the 

 need of water. The compacting of the soil by irriga- 

 tion following seeding causes a loss of moisture more 

 rapidly than from the fields sown in the other way, 

 hence the consequent need of earlier and more copious 

 irrigation. Fields in which the seed is sown in moist 

 soil usually need no irrigation for two or three months, 

 during which the grain will make an excellent growth 

 and send its roots deeper than in soil that has been 

 irrigated soon after the sowing of the seed. By the time 

 the moisture stored in the soil before sowing is evapo- 

 rated from the soil and from the plants the surface of 

 the field will be covered by the growing grain. Con- 

 sequently when water is applied evaporation from the 

 surface of the soil is not as rapid as it would be from 

 bare soil, and the soil does not bake, as in the case of 

 that irrigated when bare. Hence the soil of such fields 

 remains in much better condition than that in those 

 irrigated soon after seeding, and the grain has an 

 opportunity to make a better growth and give a larger 

 yield. 



It will be noted by referring to Table VI that the 

 wheat sown in moist soil not only required less water 

 to bring it properly to maturity, but gave a greater 

 yield. The amount of water used was about a seventh 

 greater on the field sown dry, while the yield was about 

 a seventh less than from the other field. This makes 

 quite a difference in the net returns per acre, as well 

 as in the net returns per foot of the water applied. 



Grain sown in soil that has been thoroughly moist- 

 ened to a depth of two or three feet by the application 

 of one-half to three-fourths of a foot of water will 

 need no irrigation until March or April depending 

 on the season and will need but one or two subsequent 

 irrigations to produce a good crop. As long as the 

 young grain is making a thrifty growth, water should 

 be withheld. When it begins to wilt slightly during 

 the heat of the day, or about the time it begins to 

 send up grain stalks, water should be applied. The 

 last irrigation should be given just about the time the 

 grain is in the milk. If given water between these 

 two irrigations it should receive only enough to keep it 

 growing thriftily, but not enough to make it unduly 

 rank. 



It will be observed that the amount of water used 

 in growing grains is comparatively small. This is due 

 to the time of the year during which these crops are 

 grown here, the season of sowing extending from the 

 early part of November to the middle of February. 

 The summer being too hot for them, they are grown 

 during the cool part of the year, most of the growth 

 being made from January to April, when evaporation is 

 comparatively slow. Crops of grain are sometimes 

 grown with the application of much less water than 

 given in the tables. As stated above, it is necessary 



either to irrigate the soil thoroughly before plowing or 

 to irrigate soon after sowing the seed. With one irri- 

 gation subsequent to this, a- good crop can sometimes 

 be grown in soil retentive of moisture, the total amount 

 applied not having exceeded one foot. This possibility 

 of growing grain here during the cool part of the year 

 enables us to produce a crop with less water than in 

 cooler, less arid States, where the crop is grown during 

 the warm part of the year. 



GRAPES. 



The first season after setting, grape vines need fre- 

 quent irrigation throughout the season, to enable them 

 to become well established. Two irrigations a month 

 will be beneficial in porous soils, and one irrigation per 

 month should be given in most other soils. The second 

 season the vines will do well with less frequent irriga- 

 tion. During later years the greater part of the water 

 needed to produce a crop may be applied during the 

 winter from January to March, inclusive. Water to 

 the depth of two feet may be applied to advantage in 

 most soils during this period. 



When the blossoms begin to open water should be 

 withheld until the young fruit is about the size of peas. 

 One or two thorough summer irrigations will be ample 

 to produce a good crop. No water need be applied 

 from August to January. The .total amount needed 

 during the year is not over three feet. 

 MELONS. 



Melons are planted during March along previously 

 moistened furrows. For watermelons the furrows are 

 made eight to ten feet apart, and for muskmelons, 

 about six feet apart. Water is run through the fur- 

 rows, and about two days later the seed is planted along 

 one side, just above the water line. During favorable 

 weather no further irrigation is necessary until after 

 the young plants appear. But if the weather following 

 planting be too cool for the germination of the seed, 

 the soil about them will often become too dry. In 

 such a case an irrigation a week or two after planting 

 will be important. After the first irrigation the furrow 

 should be cultivated up and a fresh one made for subse- 

 quent irrigations, which should occur about twice a 

 month during the first two months. Thereafter more 

 frequent and more copious irrigations will be desirable. 



While watermelons and muskmelons require a large 

 number of irrigations during their growth, the amount 

 applied to the crop is not correspondingly large, as is 

 shown by the record of the water applied to the water- 

 melon crops grown during the past two years. This 

 is due to the distance between the rows and to the fact 

 that during the early part of their growth only the fur- 

 row along which they are planted is moistened. Thus, 

 during the first half of the life of the crop, only a small 

 portion of the soil is kept moist ; and at no part of its 

 growth is all the surface commonly moistened. 

 Furthermore, the vines grow so rapidly that undoubt- 

 edly a larger proportion of the water is used by the 

 plants and a smaller proportion lost from the soil than 

 is the case with many crops. The covering of the sur- 

 face by the vines would also cause less loss from the 

 soil. Thus, a crop consisting of a product containing 

 a large amount of water is produced with an amount 

 of water that is smaller than might be expected. 

 ONIONS. 



Onions are irrigated through furrows, or by flood- 

 ing, the former method being preferable in most soils. 

 Seed is sown during September and October, either 



