192 



FIG CULTURE 



parasite. The difficulty of treatment arises from 

 the fact that being imbedded in the tissues of roots 

 an application that will reach them comes in con- 

 tact with fiber which it injured; and vapors and 

 solutions which kill the insects have proven equally 

 destructive to the host plants. 



The work of this worm is described by Price and 

 White as follows : ' ' The fig seems to be especially 

 susceptible to this injury in the moist soils of the 

 coast country, where the damage is frequently con- 

 siderable. * * * Over fifty species of plants 

 have been known to be infested by this pest. 9 ' 



"It is not well to allow soil to remain in the 

 greenhouse longer than a single season. It becomes 

 somewhat exhausted and is likely to become infested 

 with injurious forms of life, particularly nema- 

 todes, which cause root-rot. Most garden crops are 

 attacked by this disease. Nematodes are not trouble- 

 some in the field except in the South." (U. S., 

 Bull., 220.) 



Tobacco dust, unleached ashes and lime tend to 

 keep them in check. In Arizona the experiment 

 station has used copperas water with varied results. 

 Any solutions evaporating in the soil and leaving 

 a heavy deadly vapor will kill them ; but those now 

 in use are equally fatal to trees. Nematodes work 

 in damp places much faster than elsewhere, hence 

 drainage assists in controlling their depredations. 



The simple treatment is suggested of tilling the 



