B.C. Entomological Society. 



brush or by applying a strong spray of kerosene emulsion directly on the 

 caterpillars. The caterpillars of the other species may be quite readily 

 destroyed by burning with a torch when they are resting in their web or tent 

 on the trees. 



(3.) Spraying. — This is perhaps the simplest and most economical 

 method where quite large areas are infested, such as in parks and orchards. 

 Any reliable stomach-poison may be used, the most available being Paris 

 green and lead arsenate. Of these, lead arsenate is to be preferred on 

 account of its better adhesive qualities. The spraying should be commenced 

 as soon as possible after the caterpillars hatch, so that they may be killed 

 before much damage is done to the trees. Also the older caterpillars 

 require much stronger spraying mixtures, and as the foliage increases the 

 amount of spray necessary becomes proportionately greater; hence it is 

 doubly economical to spray early. Use 2^/4 lb. of lead arsenate to 40 

 gallons of water; or i lb. of Paris green with 2 lb. of quicklime (to prevent 

 burning) to 160 gallons of water. 



(4.) Jarring the Trees. — The caterpillars usually drop to the ground 

 when the tree on which they are feeding is jarred or shaken, so if one 

 strikes the trunk and larger branches with a padded mallet most of the 

 caterpillars will fall off, and the trunk may be banded with cotton or some 

 adhesive mixture to prevent their return up the tree. 



(5.) Banding. — Banding is more or less complementary to all the other 

 control measures in order to prevent caterpillars from infested trees near by 

 crawling on to trees which have been freed from the pests. Several 

 materials may be used for banding, but the most convenient and effective 

 material is a special tree tanglefoot prepared by the O. W. Thum Company, 

 Grand Rapids, Michigan, the makers of sticky fly-paper. This should be 

 applied as a band around the trunk about 4 or 5 inches wide and 4 or 5 feet 

 from the ground. It must be renewed, if necessary, by scraping the surface 

 and removing caterpillars which get stuck up in it. 



The natural control of these insects was discussed in a paper prepared 

 by Mr. J. D. Tothill for last year's annual meeting of this Society and will 

 be found in the report of that meeting. I would merely mention the fact 

 that insect parasites and predators, diseases, birds, weather conditions, and 

 such-like, have been responsible for the years of scarcity noted in the past 

 and will no doubt reduce the present outbreak in due time. In the mean- 

 time, however, we must make use of artificial methods of control to prevent 

 the damage to our property which must otherwise result. 



