HARROWING, CULTIVATING 147 



A second occasion when a spike-tooth harrow 

 may be used to advantage is in tilling a crop before 

 it has come up, or even afterwards. Land in corn 

 or potatoes, for example, may be run over a few 

 days after planting with a shallow- working spike- 

 tooth harrow with the teeth slanted backward; 

 this will kill the young weeds and check the escape 

 of moisture. This kind of tillage can be repeated 

 to advantage every few days until the plants are 

 two or three inches high, or until they are bruised 

 by passing between the teeth. 



The spike-tooth harrow presses down into the 

 soil and compacts it more than most other har- 

 rows. It has something of the effect of a roller. 

 For this reason it is somewhat more useful on light, 

 sandy soils which need compacting, than upon 

 heavy soils, although its compacting effect is not 

 sufficiently injurious to warrant its being discard- 

 ed for finishing and smoothing the heavier soils. 



Spring-tooth Harrow. The curved spring teeth 

 of this popular tool enable it to clear obstructions 

 easily; for this reason it is especially valuable on 

 stony, rooty or stumpy land. The teeth can be 

 set by a lever to run at various depths; this also 

 affects the quality of the work done. The spring- 

 tooth harrow leaves the soil in ridges of consider- 

 able height, which is a disadvantage in many cases, 

 as it causes the soil to lose more water from the 

 greater surface exposed to evaporation. This 

 objection may be overcome by following it with a 

 smoothing harrow. A section of smoothing har- 

 row is frequently attached behind the spring- 

 tooth harrow, or a joist or plank, say 2 inches by 6 

 inches, or a heavy iron pipe may drag behind it. 

 Any one of these devices is quite successful in 

 levelling the ridges left by the broad teeth. 



