66 SOME INSECTS INJURIOUS TO FORESTS, 



Lumber and square timbers of both soft and hard woods with the 

 bark left on the edges are frequently damaged by flatheaded and 

 roundheaded wood borers, which hatch from eggs deposited in the 

 bark before or after the lumber is sawed. There are examples of 

 losses from this character of injury amounting to from 20 to 50 per 

 cent or more. 



Telegraph and telephone poles, posts, mine props, etc., are fre- 

 quently injured before they are set in the ground, especially if the 

 bark remains on them during a few weeks after the middle of March. 



SEASONED PRODUCTS IN YARDS AND STOREHOUSES. 



Poicder-post beetles. — Hardwood lumber of all kinds, rough 

 handles, wagon stock, etc., made partially or entirely of sapwood, 

 are often reduced in value from 10 to 90 j^er cent by a class of insects 

 known as powder-post beetles. The sapwood of hickory, ash, and 

 oak is most liable to attack. Tlie reported losses from this source 

 during the past five or six years indicate that there has been an 

 average reduction in values of from 5 to 10 per cent or more. (Hop- 

 kins, 1903r, 1905rt.) 



Old hemlock and oak tanbark is often so badly damaged by vari- 

 ous insects which infest dead and dry bark that in some tanyards as 

 much as 50 to 75 per cent of the bark that is over three years old is 

 destroyed. In one tannery in West Virginia it is estimated that 

 more than $30,000 worth of hemlock bark was thus destroyed. (Hop- 

 kins, 1905«.) 



FINISHED PRODUCTS. 



The greatest loss of finished hardwood products, such as handle, 

 wagon, carriage, and machinery stock, is caused by powder-post 

 beetles. This is especially true of hickor}- and ash handles and like 

 products in the large and small storehouses of the country, including 

 the vast amount of material held in storage for the army and navy. 

 When material of this kind is once attacked it is usually Avorthless 

 for the purposes indicated, and therefore must be replaced with new 

 material. In some cases losses have amounted to from 10 to 50 per 

 cent, and it is estimated that the average losses have been as much as 

 10 per cent on nearly all sapwood material that has been in storage 

 more than one year. (Hopkins, 1903c, 1905r/.) 



UTILIZED PRODUCTS. 



Powder-post heetJes, irJiife ants, and other wood-horing inseets. — 

 The finished woodwork in implements, machinery, wagons, furniture, 

 and the inside finish in private and public buildings are often seri- 

 ously damaged l)v ])owder-])ost beetles, thus recjuiring increased de- 

 mands for new material. (Hopkins, 1903c, 1905a.) 



