DEFECTS IX TIMBER CAUSED BY INSECTS 



27 



wood of hardwoods or softwoods as unstained irregular holes from 

 one-fourth to 1 inch in diameter, which may be open, loosely ^or 

 tightly filled with powder, with granular or fibrous frass, or with 

 pellets. 21 



These and similar types of borer injury can be prevented by 

 prompt handling of the logs after they are felled. Logs, bolts, and 

 sawn or squared timbers should never be allowed to lie where cut in 

 the 

 1st 

 the 





woods, after the 



of February in 



Gulf States, or 

 after the 1st of April 

 farther north. Other 

 preventive measures 

 include : Rapid utiliza- 

 tion ; submergence of 

 logs in water, where 

 they will not be at- 

 tacked, and working 

 them up as soon as re- 

 moved from the water ; 

 sun -curing, with or 

 without the bark on 

 (care should be taken 

 to provide against ex- 

 cessive checking) ; and 

 removal of bark strips 

 from freshly sawn ma- 

 terial. The damage 

 can often be prevented 

 by peeling the bark 

 (both outer and inner) 

 from the logs or bolts, 

 timbers, or edges of 

 lumber, as the bark 

 offers a favorable place 

 under which the in- 

 sects' can lay eggs. 

 Both the outer and 

 inner bark of sawn 

 timber should always 



be carefully removed and the timbers placed where they will season 

 rapidly (1). 



DEFECTS CLASSED AS POWDER POST 



Powder post is indicated by holes from one-sixteenth to one-fourth 

 of an inch in diameter, in the surface of the wood, in the sapwood and 





Fig. 29. — Powder-posted sapwood oak veneer laid on a 

 core of chestnut (door stock) ; work of Lyctus plani- 

 collis. Note that the heartwood oak and the chestnut 

 have not been attacked 



21 The principal injury of this character found in pines, spruces, and firs is caused by 

 the pine sawyers, Monockamus spp. (fig. 25) (50) ; the loss due to pine sawyers in green 

 logs and storm-felled timber is often as high as 35 per cent. In ash the defects are 

 caused by the banded and red-headed ash borers, Neoclytus capraea Say and erythrocepha- 

 lus Fabricius ; in hickory by the banded hickory borer, Oyllen-e pietus Drury, and the 

 red-headed ash borer ; in locust by the locust borer, Cyllene roMniae Forster : in cedar 

 by the round-headed borer Callidium antennatnm Newm. (fig. 26) ; in cypress, western 

 redwoods, and cedars by flat-headed borers, Trackykele spp. Burrows made by Trachykele 

 are tightly packed with pellets of excrement, and shingle stock is full of holes "(fig. 

 27) (7). 



