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pillars pupate in cocoons attached to the bark of the trunk and branches, 

 and about tw'O weeks later the adult moths appear. The female is wingless 

 and deposits her several hundred eggs in a conspicuous whitish mass upon 

 the cocoon from which she has emerged. In this latitude the eggs mostly 

 remain upon the trees unhatched until the following spring. 



Elms and maples are our favourite city shade trees and are preferred 

 by the tussock caterpillars, but many kinds of broad-leaf trees, including 

 orchard trees, are attacked. 



Outbreaks by these caterpillars occur periodically in Montreal and 

 other cities and towns, usually giving rise to considerable alarm. If their 

 ravages were allowed to increase unchecked we should lose our finest 

 shade trees. Fortunately, the caterpillars are attacked by many insect 

 parasites, and these useful insects usually succeed in destroying the cater- 

 pillars before the most serious injury has been caused. Nevertheless, 

 many valuable trees suffer severely in these outbreaks, unless artificial 

 control measures are employed. 



Control Measures. — The caterpillars may be killed by spraying 

 with lead arsenate or Paris green. The spraying should be done while 

 the caterpillars are small, while they are more easily killed and before 

 much of the foliage is injured. One thorough spraying should be effective 

 unless the poison is washed oft' by immediate heavy rains. 



A simple and effective method is to collect and destroy the egg- 

 masses. These are whitish and easily detected upon the bark after the 

 leaves have fallen. \"aluable parasites breed within the eggs and to avoid 

 destroying man\- of these it is better to collect and burn the egg-masses 

 in the early spring, but before the eggs hatch in May. The more valuable 

 trees should be further protected from wandering caterpillars by banding 

 with cotton or "tree-tanglefoot." Complete removal of the egg-masses, 

 or thorough spraying with lead arsenate as soon as the caterpillars appear, 

 combined with banding the trunks, will protect the trees completely. 



The Fall Webworm, Hyphantria textor, is an annoying and some- 

 times rather injurious pest on elms and other broad-leaf trees. The cater- 

 pillars appear late in June or early in July and feed in colonies gradually 

 covering the branch attacked with an irregular unsightly web. The tents 

 of this species are readily distinguished from those of the common American 

 Tent Caterpillars by the irregular appearance, gradually covering the 

 leaves of a large portion of the branch, and by their presence in the latter 

 part of the season. 



