Specific Pests 153 



or even like wood-borers, penetrating into the interior. 

 They are especially obnoxious in conifers and more in 

 younger than in older trees. The most important one 

 damaging trees is perhaps the — 



White Pine Weevil; it attacks the leading shoot in young 

 trees, sometimes year after year, causing its death and lead- 

 ing to deformity by multiplying the leaders, one or more 

 side branches taking up the leadership. 



A protective cover of soap wash (one pound to a hundred 

 and fifty gallons of water), to which Paris Green is added, 

 may keep the weevil off. Infested branches should be cut 

 off and burned and the formation of a single proper leader 

 regulated by proper pruning. In plantations, baiting and 

 collecting the beetles is probably the only practical remedy 

 against the pests. 



Bark Beetles are small weevils, generally not exceeding 

 one-eighth of an inch, with very short snouts, of cylindrical 

 form, and black, brown or gray color. Boring little lioles 

 through the bark into the soft layers of cambium and sap- 

 wood in early spring, they enter and make a burrow close 

 under the bark, in which the eggs are laid; these soon hatch 

 and the larvae continue the burrow in the cambium or wood, 

 in galleries characteristic in outline for each species. At 

 the ends of these channels they pupate and (in some of the 

 species) within a month of the egg-laying the young beetles 

 seek the old opening or a new one to mate and repeat the 

 cycle, several broods being developed in the summer. 



Remedies, as described on page 147, consist in removal 

 of infected parts or trees, baiting, and keeping trees in vig- 

 orous condition. 



Round-headed Wood-borers are large beetles with elon- 

 gated body, greatly varied in color, recognized easily by 

 their long feelers or antenna?, which are longer than their 



