128 FARM MACHINERY 



There is less tendency for the stub runner to ride over 

 trash than the curved runner. Fig. 94 shows a stub 

 runner. The stub runner cannot be used in stony or 

 stumpy land. 



The single-disk furrow opener has good penetration and 

 is desired in some localities for that reason. It is also 

 better adapted to trashy ground, the disks cutting their 

 way through. The disks may or may not reduce draft; 



FIG. 95 THE SINGLE-DISK FURROW OPENER 



at any rate, the planter is not a heavy-draft implement. 

 Penetration is not often needed ; more often the planter 

 has a tendency to run too deep. The single-disk planter 

 throws the soil out one way, and it is difficult for the 

 wheels to cover the seed. The disk has a bearing to wear 

 out, which the runner has not. 



The double disk cuts through trash to good advantage, 

 but does not have the penetration of the single disk. It 



