IRRIGATION FOR THK ORCHARD. 287 



deptfis of working the ground are better, but a hard- 

 ened layer at some depth generally results. It may 

 have been made when the present orchard lands were 

 grain fields or the pasture grounds of vast herds wallow- 

 ing over them in wet seasons. The existence of the 

 artificially compressed layer or of a natural hard-pan 

 just beneath the tilled surface is manifest to the irri- 

 gator by lack of penetration of the water. After 

 running a short time in furrows prepared for the pur- 

 pose, the resistance proves too great for the water to 

 sink to a depth where it can be of use to the root system, 

 and it wets the surface soil from furrow to furrow, 

 where the need of moisture is least and evaporation is 

 greatest. 



It is estimated that in summer 60 per cent, of 

 irrigating water thus applied is lost. Some practical 

 and economical method of subirrigation would prevent 

 this loss. A California man has invented a point or 

 hook to run beneath the line of draft at the bottom of 

 the furrow. This attachment is fastened to the point 

 of the share in front and any blacksmith can make it. 

 This tool will cut through the somewhat impervious 

 layer of soil and make a diredl way for the water to 

 enter the lower stratum to be saved and utilized. 

 Dependent upon the nature of the soil, the plow may 

 be drawn by two, three or four horses. In ordinary 

 ground two good horses will draw it at a depth of 

 thirteen inches, where loose soil is usually found 

 beneath the layer of hard-pan. Water running in such 

 furrows immediately over the channel cut through the 

 hard-pan wets below first, and after flowing some time 

 moistens the surface beyond the furrows. 



