EXPERIMENT STATION BULLETINS. 



605 



When stable manure can not be easily obtained, cover crops may be used 

 to keep up the humus supply. Oats sown at the time of the last cultiva' 

 tion, or about the middle of August, at the rate of two bushels per acre 

 will pro\dde a good supply of organic matter to turn under the next 

 spring. Clovers, vetch, or rye may be used providing they are drilled in 

 between the rows and turned under very early in the spring. Otherwise 

 they may become established among the plants and considerable hand 

 labor may be necessary to eradicate them. 



Fig. 5. — Black raspberry plant before and after pruning in the spring. 



