24 THE POTATO 



the disk harrow. These tools work deeper than the 

 Acme harrow, and may be used to prepare the soil to a 

 depth of four to six inches, which seems to be as deep as 

 is necessary. Few farmers prepare land to this depth, 

 as it requires three horses on a six-foot harrow on a loam 

 soil. Two to 2^ inches is more common. Harrows 

 differ in their action; thus, the spring-toothed harrow 



FIG. 9 DOUBLE-ACTION CUTAWAY HARROW 



and the smoothing or spike-tooth harrow tend to com- 

 pact the soil while fining it, while the disk type (Figs. 

 8 and 9) and Acme harrows tend to lighten it and make 

 it more open when they fine it. For potatoes and corn 

 the latter are preferable, while for wheat the former. 

 Whatever tool is used the land should be well fitted. 

 Few farmers prepare the land well enough, and many 



