Some Special Injurious Insects 



171 



duced in a season. Young scales are possibly carried 

 from orchard to orchard by birds, winds and other 

 agencies, but most usually on nursery stock. Lady 

 bugs (^[247) and parasites are important natural 

 enemies, but effective control depends on the use of 

 contact poisons (^[232c) when the trees are dormant, 

 preference being given to the lime-sulphur wash. 

 (See appendix B). 



237. Tent Caterpillars are often found in fruit trees. 

 They are easily discovered in the spring by their large 

 webs supported on the branches. Small bunches of eggs, 

 like those shown in 

 Fig. 108c, may be 

 found much earlier. 

 These eggs are laid 

 late in the summer 

 and covered by a 

 sticky substance to 

 protect them from 

 the winter rains. 

 They hatch out usu- 

 ally just about the 

 time the buds open 

 and the caterpil- 

 lars feed on the 

 young buds and 

 leaves. The cater- 

 pillars soon spin a 

 delicate cloth -like 

 web or tent, to 

 which they retire at 

 night, and in bad 



Weather. These Fig. 108. The tent-caterpillar, a and b, larvae; 



caterpillars are SS^** * c c n; *' full - grown ' Mter 



