6 MASS, EXPERIMENT STATION BULLETIN 439 



Brush-breaker plows were used to turn over new land where brush, stumps, 

 trees, and boulders had been cleared with bulldozers. Shrubs and bushes were 

 plowed under with these heavy-duty plows, and roots, small stumps, and stones 

 were turned up and removed. For vegetable crops and sometimes for potatoes 

 a deep tiller was used to break up subsoil and to rake out stumps, roots, and 

 stones not removed previousl}'. 



Figure 2. 



A. Large Bulldozer Clearing Woodland for Orchard. 



B. Bushes Are Removed with a Small Bulldozer. 



