56 



are infested. In plants the vitality is so lowered that their cultiva- 

 tion is profitless, and hairy root on deciduous trees and chlorosis 

 of the citrus trees are attributed to its influence. The infestation 

 can be located with certainty only by examining the roots, but 

 when found to any serious extent it cannot be mistaken. No 



Nematode galls on cucumber root. 



remedy is known for it, and we can only be careful not to plant 

 infested potatoes or trees, or use infested land for trees or plants 

 liable to it. Infested land can be used for grain, and if beets are 

 planted in it and pulled and destroyed when half grown, before the 

 mature worms escape into the soil, its condition is said to be much 

 improved. 



