402 THE SMALL GRAINS 



use of the packer. Later in the summer there must be 

 sufficient cultivation to kill weeds. When the weeds get 

 too large for the toothed harrow, -the slicker (Fig. 129), the 

 knife weeder (Fig. 130), or the disk harrow may be used. 

 In a few places in Washington, a method of right lapping 

 for summer tillage, with a cut-away disk harrow (Fig. 131), 

 has been practiced for some time, in which no plowing is 

 done. With this implement, the right half laps over, in 



FIG. 130. The knife weeder, - an efficient implement, but expensive. 



the next round, all the work done by the left half. There 

 are 2 cultivations, one very early 4 inches deep, and the 

 second 5 to 6 inches dee'p. If the weeds are bad, there 

 may be a third cultivation, or the harrow or slicker may 

 be used afterward. 



In a large portion of the Columbia Basin, early spring 

 disking for summer tillage is done before plowing. Some 

 double-disk and then use the toothed harrow. Moisture 

 is thus conserved early and rapidly, weed seeds are caused 

 to germinate, and the young weeds are afterward de- 

 stroyed by the plow. The land is plowed from 4 to 6 



