INSECT INJURIES TO FOREST PRODUCTS. 7 



Damage by powder-post insects to many kinds of articles can be pre- 

 vented and at the same time the material otherwise benefited by treat- 

 ing the sapwood with linseed oil or kerosene, either by immersing it 

 in the oil or by applying the oil with a brush, the application to be 

 made as soon as possible after the articles are finished from recently 

 seasoned, uninjured stock. 



Past and Pbesent Conditions op Powder-Post Injury. 



Up to 1906 there were a great many reports of extensive losses of 

 valuable material from the ravages of powder-post beetles which 

 were seriously affecting all industries involved in the manufacture, 

 sale, and utilization of the classes of hardwood products affected by 

 them. In response to these reports and accompanying appeals to the 

 -Department of Agriculture for information on causes and remedies, 

 the problem was thoroughly investigated and specific advice and in- 

 structions relating to practical methods of control and prevention 

 have been widely disseminated, both through publications of the 

 Department and special correspondence. 



Reports of present conditions from our principal correspondents, 

 together with the less frequent requests for advice, indicate that 

 the disseminated information has been extensively utilized and that 

 it has been worth many millions of dollars toward eliminating the 

 losses and reducing the drain on the limited supply of the kinds of 

 timber required to replenish the damaged and destroyed material. 



The army and navy stores of handles, tent poles, wheelbarrows, 

 oars, and many other hardwood articles have suffered severely from 

 powder-post damage, involving an enormous loss, but the carrying 

 out of the information already supplied has evidently contributed 

 greatly toward the elimination of this source of loss to the Gov- 

 ernment. 



Tan Baek. 



Damage to hemlock and oak tan bark by the class of insects which 

 in some cases has been so destructive to these products in the past can 

 be easily prevented without cost, as follows: 



(1) Utilize the bark within three years from the time it is taken 

 from the trees. 



(2) Prevent the accumulation in the yards and store sheds of old 

 bark and waste material in which the insects can breed. 



These simple methods have been extensively adopted since their 

 recommendation in correspondence and publications between about 

 1894 and 1904, and afford one of the most striking examples of the 

 value of expert information on the peculiar habits of insects and of 

 how millions of dollars can be saved without cost through a simple 

 adjustment in methods of utilization. 



[Cir. 128] 



