A 



E- 251 



IEJITED STATES DEEARTMSNT OE AC-EI 

 BUREAU 01- EMMGLOGY 

 Washington, D. C. 



11.2.1* *^*w«* 



Forest Entomology Brief 59 



August 1, 1924 



BRIEE IHTOBM4!riQ2ff OH THE PROTECTION OE LOG QfiBIMS 

 MD RUSTIC WORK EROM INJURIOUS INSECTS 



Character and Extent of Injury 



Considerable damage to the unbarked logs of the principal woods 

 used in the construction of leg cabins and rustic work is caused "by in- 

 sects. Woods cut at certain seasons of the year are subject to attack 

 "by "beetles, which riddle the bark with holes, causing sawdust-like bor- 

 ings to fall out and cover the wood; and by the larvae, or grubs, of 

 wood-boring beetles, which mine the inner bark, causing it to loosen and 

 fall off, and which bore into the sapwood and sometimes the hear two od of 

 logs, making large ho'.es and often reducing them almost to dust within 

 a few months. This damage causes large financial loss, annoyance, and 

 unsightly condition of the material. 



It has been found that by cutting the wood at certain seasons of 

 the year and by treating it with protective, repellent, or Insecticidal 

 substances, practically all insect damage can be prevented or held in 

 check. 



Evidence of Infestation 



In most instances the injury can be detected by the presence of 

 the characteristic piles of reddish-brown or whitish particles of boring 

 dust, or shredded wood fiber, which the irsect makes while working In the 

 bark or wood and which it pushes to the outside in order to clear its 

 gallery. 



Remedy 



The beetles or grubs in the bark and wood can be killed by thor- 

 oughly saturating all parts with liquid orthodichlcrcbenzene. As it is 

 necessary for the solution to penetrate the wood and reach the insect in 

 order to kill it, great care must be taken to apply the liquid thoroughly;, 

 This solution is colorless and will not stain. It has a slight odor which 

 disappears after a short while. Orthocichlorobenzene can be effectively 

 applied either with a brush or a forceful sprayer. The spraying method is 

 preferred since it saves much time and labor. One pint will treat a chair. 

 Three gallons is sufficient to treat 100 square feet of log surface. 



