168 IRRIGATION FARMING. 



throwing up from each side a good slice with a two-horse 

 stirring plow. This will cover the potatoes to a good 

 depth and leave them in ridges for irrigation. We 

 always make it a point to give the prepared ground 

 a good flooding before planting, unless the heavens have 

 wept copiously to moisten the ground. We plant, in 

 Colorado, from May 20 to June 10. For seed \ve 

 prefer the half-cut tuber, although this is a matter of 

 one's own judgment. 



When the sprouts appear above ground we go over 

 the patch with a slant-tooth drag to loosen the soil. 

 There is no danger of injuring the plant in this way. 

 We are not able to say just when potatoes should be irri- 

 gated. In that, as in size of seed, no rule will hold 

 good. Some varieties require more water than do others, 

 and some soils require more than others. Water 

 applied too soon will often turn the vines yellow and 

 permanently check their growth. On the other hand, 

 if the ground is very dry at the period when potatoes 

 are setting, as we term the formation of the young 

 tubers, it often happens that no after application of the 

 water will remedy the matter, and a short crop is the 

 result. As a general rule, it is much better for the crop 

 that the vines should attain a good degree of growtli and 

 be well in blossom before water is applied, but there is 

 no fixed rule as to this. When the ground gets very 

 dry and hot, and the vines turn dark-colored and cease 

 to grow, water becomes a necessity at no matter what 

 season, unless the crop has already or nearly matured. 



If the spring has been cold and very backward, ami 

 the subsoil is still lacking in warmth, it will be found fatal 

 to the potato plant to apply water, even if the soil is 

 very dry. It has been found that soils that are heavily 

 manured will take water at an earlier date in the sprinir 

 without injury to the plant than will poor, thin soils; also, 

 ly reason of the undecayed manure applied, it is neces- 



