]28 THE GYPSY MOTH. 



the canker-worm, and a part of the expense was borne by 

 the town. The bark of the tree was first scraped or planed 

 at a height of about six feet from the ground, so that a 

 reasonably smooth surface about six inches wide was formed 

 extending around the trunk. A band of cotton waste was 

 then placed on the smooth surface about the trunk, and a 

 band of tarred paper about the cotton. A cord al)out the 

 paper drew it closely to the cotton waste, which was thus 

 pressed firmly against the tree. This waste was placed 

 beneath the paper to prevent the newh^ hatched caterpillars 

 (which can pass through very minute crevices) from crawling 

 ^.■^^ff.^^' under it and so on up the tree. The tarred 

 paper was then covered with a mixture con- 

 sisting of three parts tree ink, one part pine 

 tar and one part petroleum (residuum oil). 

 The cotton waste prevented this mixture 

 from penetrating to the bark of the tree. 

 Fig. 7 shows the band about the tree with 

 the string removed and a piece torn away 

 to show the cotton packing. The black 

 „ „ ^ , ])and represents that part of the paper 



Fig. 7. Tarred paper -C^ J- J- ^ 



band. which was covered with the mixture. 



Tacks and staples were used where necessary to draw the 

 paper and string closely to the tree. 



It was necessary at first to apply several coats of the mixt- 

 ure, so that the tarred paper might become so well saturated 

 that it would not absorb subsequent applications. When 

 this was efiected, an application was made at least twice a 

 week for the rest of the season where trees on dusty streets 

 were banded, but it was not required so often (except in very 

 hot, dry weather) in orchards or woodland. As a result of 

 the banding, most of the caterpillars were kept out of trees 

 along the streets, and therefore there was little danger of 

 their being distributed along the highways in such numbers 

 as in former years. In badly infested localities this method 

 can only be efi*ective when the eggs on the trees have been 

 destroyed and a large part of the egg-clusters in the vicinity 

 gathered. Otherwise, the massing caterpillars will bridge 

 the tarred paper with their bodies and on this bridge others 

 will cross, or else the young caterpillars will be borne on the 



