LUTHER BURBANK 



They are obtained by the man who understands 

 the bad effects of growing the same crop on one 

 field year after year, and who knows that these 

 effects can be avoided by making a change in 

 crops. 



Every horticulturist and every agriculturist 

 should study what follows carefully. It tells why 

 failures come, and why rotation forestalls such 

 failures. 



There are at least four important reasons why 

 rotation of crops is necessary. 



In the first place, insects which often gather in 

 great numbers about certain plants are destroyed, 

 or at least their number is reduced when other 

 crops are grown on the land. This is because 

 certain insects are adapted to depend upon certain 

 plants for their nourishment. Lilies and amaryllis 

 are often almost completely destroyed by such 

 insects as mites, small centipedes, wire worms, eel- 

 worms, etc. 



Absolutely new, uncultivated soils seldom are 

 troubled. It is mostly in gardens where plants 

 from various quarters are grown that difficulty 

 occurs. 



These pests gather around the lower part of the 

 bulb and if the bulbs are left in the same place 

 several years the insects often destroy them com- 

 pletely. 



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