ARID AGRICULTURE. 61 



and good work cannot be done with a large disc. 

 The disc should be used to break up the surface 

 sod or stubble immediately after harvesting, and 

 where this is done, it will be found that plowing 

 will produce a much better seed bed. Turning 

 under the disced surface also leaves less air space 

 and the soil reservoir is more perfect. The disc 

 is useful to destroy weeds on summer tillage, but 

 it must be used when the weeds are small. It 

 will merely cultivate large weeds. Always lap 

 the disc one-half, which double-discs the ground 

 and leaves it level. The disc is very useful for 

 certain forms of cultivation, especially with al- 

 falfa. The new alfalfa harrow consisting of a 

 series of spikes arranged in disc form seems to 

 be one of the best tools for the cultivation of 

 alfalfa. 



Perhaps the Acme harrow is one of the most 

 useful soil pulverizers for the farm. It does 

 most excellent work where shallow surface culti- 

 vation is required. The spring-tooth harrow is 

 a useful implement for harrowing compact and 

 tough soils. There are some new harrows now 

 being constructed on the general plan of the old 

 drag or toothed harrow, but with modified teeth. 

 One is a small disc three or four inches in diam- 

 eter, riveted horizontally to the lower end of the 

 harrow tooth. Another has the lower end of the 

 harrow tooth bent at right angles and flattened 

 and sharpened in the form of a knife blade. 



