LEPIDOPTERA. 363 



far from the trees upon which Ihcy have lived in the caterpillar 

 state. Canker-worms are therefore naturally confined to a 

 very limited space, from which they spread year after year. 

 Accident, however, will often carry them far from their native 

 haunts, and in this way, probably, they have extended to 

 places remote from each other. Where they have become 

 established, and have been neglected, their ravages are often 

 very great. In the early part of the season the canker-worms 

 do not attract much attention ; but it is in June, when they 

 become extremely voracious, that the mischief they have done 

 is rendered apparent, when we have before us the melancholy 

 siffht of the foliage of our fruit-trees and of our noble elms 

 reduced to withered and lifeless shreds, and whole orchards 

 looking as if they had been suddenly scorched with fire. 



In order to protect our trees from the ravages of canker- 

 worms, where these looping spoilers abound, it should be our 

 aim, if possible, to prevent the wingless females from ascend- 

 ing the trees to deposit their eggs. This can be done by the 

 application of tar around the body of the tree, either directly 

 on the bark, as has been the most common practice, or, what 

 is better, over a broad belt of clay-mortar, or on strips of old 

 canvass or of sti'ong paper, from six to twelve inches wide, 

 fastened around the trunk with strings. The tar must be ap- 

 plied as early as the first of November, and perhaps in Octo- 

 ber, and it should be renewed daily as long as the insects 

 continue rising; after which the bands may be removed, and 

 the tar should be entirely scraped from the bark. When all 

 this has been properly and seasonably done, it has proved 

 effectual. The time, labor, and expense attending the use of 

 tar, and the injury that it does to the trees when allowed to run 

 and remain on the bark, have caused many persons to neglect 

 this method, and some to try various modifications of it, and 

 other expedients. Among the modifications may be mentioned 

 a horizontal and close-fitting collar of boards, fastened around 

 the trunk, and smeared beneath with tar; or four boards, nailed 

 together, like a box without top or bottom, around the base of 

 the tree, to receive the tar on the outside. These can be used 

 to protect a few choice trees in a garden, or around a house or 



