INJURIOUS INSECTS AND FUNGI. 275 



then to destroy the larvae by spraying with Paris green used 

 as for the elm-beetle, making two applications, one when 

 the first eggs hatch and then again in from five to eight 

 days, according to the weather, or when all of the eggs are 

 hatched out. Success in this work depends upon how much 

 Paris green is used and how thoroughly the foliage is 

 covered with it. For the amount of Paris green to use and 

 method of application see " Treatment of the Elm-beetle," 

 pages 269 and 270. 



BORERS. The maple-borer, Fig. 156, has already been 

 described, but there are many ornamental trees besides the 



FIG. 158. CANKER-WORM. 



(Riley : Circular No. 9, 2d Series, Dept. Agr., Fig. 3.) 



maple that are injured by borers. The thorns, flowering 

 apple, and some other trees are injured by the ROUND- 



a b c d 



FIG. 159. ROUND-HEADED APPLE-BORER. 



(Chittenden : Circular No. 32, 2d Series, Dept. Agr., Fig. 1.) 



