284 MISCELLANEOUS FARM SUBJECTS 



The cost of leveling depends altogether upon the character of 

 the land, some tracts requiring a great deal more work than others. 

 However, from the most favorable conditions to the most unfavor- 

 able under which leveling is done, the cost ranges from about $5 

 to $25 per acre, with the average between $12 and $17. (Ex. S. 

 Cir. 188.) 



Choice of an Irrigation Method. The choice of method is to 

 be made in accordance with several conditions: 



m The slope of the land. 



(2) The character of the crop. 



(3) The character of the soil. 



(4) The labor requirement. 



(5) Ease of cultivation after irrigation. (F. B. 138.) 

 Methods of Applying Water. The methods in which applica- 

 tion is made in field and garden practice include the following: 



(1) Free flooding, or running water without restraint except 

 that afforded by the banks of the laterals conveying it. 



(2) Flooding in contour checks, or irregular-shaped inclos- 

 ures which are determined in size and shape by the inequalities of 

 the surface. 



(3) Flooding in rectangular checks, or inclosures which are 

 approximately of equal size and with level bottoms. 



(4) Depressed beds, with raised ditches on the levees which 

 hold the water until it soaks away among the inclosed plants a 

 garden modification of the rectangular-check system. 



(5) Ridge irrigation, in which plants are grown on the sides 

 or at the bases of raised ditches a simple form of depressed-bed irri- 

 gation. 



(6) Furrow flowing, or running water in one or more fur- 

 rows between the rows of crops grown in that way. 



(7) Raised-bed irrigation, in which the water is taken by 

 seepage and capillary action from a small ditch on each side a mod- 

 ification of the furrow system. 



(8) Subirrigation, or distribution by means of pipes with suit- 

 able outlets, or from blind ditches filled with material permitting cir- 

 culation of water which will reach the plant roots by capillary action.. 



(9) Underflow irrigation, by which the ground water is raised 

 by percolation from ditches at intervals of considerable distance 

 the plant roots being reached directly or by capillary movement. 



(10) Distribution under pressure in underground pipes, with 

 standpipes and connections for sprinkling. (Ex. S. Bui. 145.) 



Flooding Method. Flooding the surface of land from field 

 ditches or laterals is the most common way of wetting soil. This 

 method is common in the Rocky Mountain States, and the condi- 

 tions which prevail there seem to be well adapted to this mode of 

 applying water. It can be used on quite steep slopes and in vari- 

 ous other ways fits in with the requirements of the irrigator on the 

 more elevated lands. It consists in leveling, grading, and smooth- 

 ing the surface of fields to such a degree that water will readily flow 

 over it. As a means of distributing the water over the field small 



