42 INSECTS OF ECONOMIC IMPORTANCE 



phur solution at the same rate l)ut without the soap. 

 Arsenate of lead may be added if desired. 



In case of the green apple aphid especially it 

 may be necessary to make later applications of the 

 nicotine sulphate owing- to repeated infestations in 

 June and July. It has proven advantageous at this 

 time to add rather large quantities of quick lime or 

 hydrated lime ^^ to the nicotine sulphate and water, 

 leaving out the soap. The mixture of nicotine sul- 

 phate and lime seems to have a deterrent effect on 

 the aphids in addition to its killing properties. 



The fall canker-worm (Alsophila pometaria) 

 Order — Lepidoptera. Manual, p. 2y6 



Moths emerge in late fall and the wingless fe- 

 males lay their eggs in clusters on bark; eggs rest 

 over winter and hatch in early May; larvse which 

 are loopers and have only 3 pairs of abdominal legs 

 feed for a month and in June and July go into the 

 ground to change to pup?e in dense cocoons, and re- 

 main here until fall when the moths appear again; 

 one brood a year. 



The SPRING CANKER-WORM ^^ (Paleacrtta vernata) 

 Order — Lepidoptera. Manual, p. 275 



Moths emerge in March and April and lay their 

 eggs in small clusters in crevices of the bark ; cater- 

 pillars which are loopers and have only 2 pairs of 

 abdominal legs hatch in May and in June and July 

 go into the ground where they remain as pupae 

 until the next spring; one brood a year; the female 

 is gray and wingless and bears two transverse rows 

 of short spines on the dorsal side of each of the 

 first seven segments of her abdomen; the spring 



10 Hodgkiss— N. Y. State Expt. Stat, Bull. 461. 



11 Qiiaintance— U. S. Bu. Ent., Bull. 68, Pt. IL 



