INSECT DEPREDATIONS IN NORTH AMERICAN FORESTS. 83 



the disseminated information has been extensively utilized and (Imt 

 it has been Avorth many millions of dollars toward eliminatiii<i: the 

 losses and reducin<^ the chain on the limited supply of the kinds of 

 timber required to replenish the dama»ed and destroyed material. 



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

 oars, and many other hardwood articles have suti'ered severely from 

 powder-post dama^je, involving an enormous loss, but the carrying 

 out of the information already supplied has evidently contributed 

 greatly towaril the elimination of lliis source of loss to the Gov- 

 ernment. 



TA.N I'.AKK. 



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 nnd 1004. and afi'ord 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. 



T'th.izkd Prodx'cts. 



Damage and loss from insect injuries to timlier and other woodwork 

 in structures of various kinds, to telephone and telegraph jwles, posts, 

 railroad ties, mine props, etc., can be prevented to a large extent 

 through the adoption of the proper methods of management or of 

 treating the material with preservatives before and after it is utilized. 



TIMBKBS AN'l) WOODWOKK IN .STinCTVKK.S. 



Injuries to timbers and woodwork in dwellings, outbuildings, 

 bridges, etc., by powder-post insects can be prevented as follows: 



( 1) Use nothing but heart wood f<u' the concealed parts most liable 

 to damage. 



(2) If it is necessary to use all or part sapwood material, attack 

 can be prevented by treating the sap portions with kerosene, coal tar, 

 creosote, or linseed oil. Facilities for future treatment can be pro- 

 vided wherever the rough or finished woodwork is exposed, as in 

 outbuildings, bridges, etc., if care is taken to expose the sapwood 

 portions. 



