INSECT INJURIES TO FOREST PRODUCTS. | 
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 PRESENT CONDITIONS OF 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 BARK. 
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 tan 
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] 
