244 



WOOD AND FOREST. 



F'tg. ^'4. Work of Round-Headed and 

 Flat-Headed Borers in Pine: a, Worlc 

 of ro.iiid-lieaded borers, "sawyer," il/o«o- 

 hamllits sp.: by Ergatcs spicttlallts\ c, Worlc 

 of flat-headed borer, Bupri!stis, larva 

 and adult. {Agric. Tear Book. 1'I04, 

 Fig. 46, p. 385.] 



The pine sawyers are 

 among the most trouble- 

 some pests in the mill 

 j-ard, and their large, 

 white larvae often do 

 much damage to logs by 

 eating great holes thru 

 their solid interior. While 

 burrowing in the wood 

 the larvae make a pecu- 

 liar grating sound that 

 may be heard on quiet 

 nights at a considerable 

 distance. This is a fa- 

 miliar sound in the lum- 

 ber camps of the North, 

 and has probably given rise to the name of the pine sawyers by which these 

 insects are known. {Forestry Bulletin, No. 22, p. 58.) 



Powder-post beetles, Fig. 96. This is a class of insects representing 

 two or three families of beetles, the larvae of which infest and convert into 

 fine powder many different kinds of dry and seasoned wood products, such 

 as hickory and ash handles, wagon spokes, lumber, etc., when wholly or in 

 part from the sap-wood of trees. Oak and hemlock tan-bark is sometimes 

 injured to a great extent, and the structural tin-ibers of old houses, barns, 

 etc, are often seriously injured, while hop poles and like products are at- 

 tacked by one set of these insects, the adults of which burrow into the wood 

 for the purpose of 

 depositing their 

 eggs, (Hopkins, 



Forestry Bulletin. 

 No. 4.S, p. 11.) 



Timber iponiis. 

 Fig 97. This class 

 of true wood-bor- 

 ing "worms." or 

 grubs, are the lar- 

 vae of beetles. 

 They enter the 

 wood from eggs de- 

 posited in wounds 

 in living trees, 

 from which they 

 burrow deep into 

 the heart- wood. 

 Generation after 



generation may '">'• "S- Hemlock Killed by Buprestid Worms. 



'^ •' Hoquiara, Washingrton. I .s. Forest Service. 



