JIOTII CATERPILLARS AND I'l.ANT-LICE. 



59 



Fio. 11. — Pisiodee strobi: beetle at left; a. 

 larva; b, pupa — pnlarfjed about three 

 times {from Packartl). 



spots, as sliowu in the accompanying illustration (fig. 11). It is iJiovided witli a latlier long 

 rostrum or snout to which are attached its elbowed antenna-. The larva, which is white and foot- 

 less, is illustrated at «, and the pupa, also white, is fi<,'ured at h. 



This weevil is one of the lirst si)riiig visitants in the Xorth, occurring as early as ^Nfarch about 

 Washington City and in April or -\Iay farther north. Its eggs are deposited on the teiniinal shoots 

 of pine, particularly of young trees, but sometimes also iu the bark of old trees. The larva, when 

 hatched, bores into the pith or mines the sapwood. Toward the 

 end of summer it attains full growth, when it goes into hiberna- 

 tion until the uext spring, transforming to pupa and soou after- 

 ward to the mature or beetle form. The presence of this insect in 

 a tree is first manifested by the wilting of the leading shoots, which 

 becomes most evident toward the close of summer. The identity 

 of the species at work may be established at once from its iieculiar 

 cells beneath the bark. (See fig. 12.) These cells, which are 

 destined for its wiuter nest and for further transformation, are 

 sunk into the pith and covered over with long fibers of chipped 

 wood. When a terminal shoot of a small tree becomes filled in the summer with these larva-, to 

 the number sometimes of a score or more, the shoot, with its lateral branches, as well as the stock 

 below, wilt and gradually die, the bark becomes loosened, pitch oozes out, and by autumn the 

 shoot turns black, and the bark is covered with masses of iiitch, A tree thus damaged will fail 

 sometimes for several successive seasons to send out a new terminal shoot, with the result that 



the lateral shoots continue to grow, and the tree becomes more or lesa 

 distorted. 



Owners and overseers of pine groves will do well to make a i)ractice 

 of examining the young trees each year, say iu August, and when one 

 with a wilting terminal shoot is found to cut or break it off and commit 

 it to the flames. With every blighted twig thus treated from a dozeu to 

 fifty or more weevils will be destroyed, and thus the numbers of the 

 insects for the coming year will be greatly lessened. All dead growth 

 or such trees as have from any cause been injured beyond recovery 

 and which might serve as centers of infestation by harboring this weevil 

 or other injurious species should be similarly treated. What is most 

 needed is a preventive, and for this purpose a good thick fish-oil soap 

 mixed with Paris green and carbolic acid, in the proportion of about a 

 pound of the former and a quart of the latter to 100 gallons of the wash, 

 is recommended. It should be sprayed in April and ^lay on the terminal 

 shoots of the trees and repeated at the end of a month if necessary. 



MOTH CATERPILLARS AND PLANT-LICE ON TRUNKS AND LIMBS. 



The trunks and limbs of i>ine are also subject to the attack of sev- 

 eral insects besides those iu the order Coleoptera that have been men- 

 tioned. Of these are three tortricid moths of the genus Eetinia, which 

 aflect the pitch and other pines. Two other moths of similar habits to 

 the above occur on White Tine, wounding the trunk below the insertion 

 of the branches and causing the resinous sap to exude. These are 

 the pitch drop worm {Piuipc.stis zimmermanni Grote) aud llurmonia 



pinl Kell. 



The same remedies advised for other boring species, aud particularly 

 those specified to be used against the white-pine weevil, are indicated for the present class of 



insects. 



Several species of plant-lice attect the White Pine. The white-pine aphis {Lavhnus strohi 

 Fitch) is very abundant iu the Northern States, living in colonies on tlie branches of trees and 

 puncturing and extracting their juices. The so-called "pine blight,'' Chermes innicorticis Fitch, is 

 sometimes very destructive, its pre.sence being manifested by large patches of a white, floccnlent 



Fig. 12. — Fissodes itrobi : a, larval 

 mines under bark; 6, pupal 

 cells — natural size (from Riley). 



