GENERA I. PRA ( ' TICE. ENEMIES. 



491 



the ground. This practice cleanses the ground of weeds, enriches and improves the 

 staple, whilst destroying the chrysalides of the moths, 



Despite every precaution some female moths gain access to the trees and deposit their 

 cg'^s in the ends of pruned shoots ; hence it has been found that deferring pruning until 

 February is advantageous where the enemy abounds. So many eggs were discovered 

 between the bark and the wood at the ends of shoots pruned in the autumn in Mr. Lee 

 Campbell's fruit garden, that the infested ends had to be cut farther back in spring, and 

 it was computed by the owner of the trees that in burning these ends six millions 

 were destroyed in one season, or sufficient to prevent a devastating horde of caterpillars. 



Caterpillar infestations are largely induced by the neglected condition of garden and 

 orchard hedges. Hedges ought to be kept trimmed, but the cutting should be deferred 



Fig. 92. WI.NTBB MOTH CATBBPILLABS INVESTING APPLE LEAVES AND BI.OSSOH. 



until early spring, so as to permit insects to deposit their eggs on the twigs, removing 

 them before hatching. Moths, however, travel quickly over the space between hedges, 

 copses, and woods to orchards ; therefore, to prevent insect invasion, insectivorous birds 



should be preserved. 



p p 2 



