2 INSECT INJURIES TO FOREST PRODUCTS. 
tinue to work in mine props after they have been placed in the mine, 
and in logs and other material used for the construction of cabins, 
rustic houses, etc., and in round timbers generally. 
The products from saplings, such as hickory hoop poles and like 
material, are often seriously injured or rendered worthless by round- 
headed and flatheaded borers and wood-boring beetles, sometimes 
resulting in a loss of from 50 to 100 per cent of the merchantable 
product. 
Stave and shingle bolts left in moist, shady places in the woods or 
in close piles during -the summer months are often attacked by 
ambrosia beetles and timber beetles. The value of the product is 
often reduced, as a consequence, from 10 to 50 per cent or more. 
Handle and wagon stock in the rough is especially lable to injury 
by ambrosia beetles and roundheaded Worant Hickory and ash bolts 
from which the bark is not removed are almost certain to be greatly 
damaged if the logs and bolts cut from living trees during the winter 
and spring are held over for a few weeks after the middle of March 
or first of April. 
Pulp wood, and cord wood for fuel and other purposes, cut during 
the winter and spring and left in the woods for a few weeks or 
months or in close piles after the beginning of the warm weather, are 
sometimes riddled with wormholes or converted into sawdust borings, 
causing a loss of from 10 to 100 per cent. One example reported 
from near Munising, Mich., represents a loss of $5,000 from injury to 
spruce and fir pulp wood cut in the winter and kept in piles over 
summer. 
MANUFACTURED UNSEASONED PRODUCTS. 
Ambrosia beetles and other wood borers.—F¥reshly sawed hard- 
wood placed in close piles during warm, damp weather during the 
period from June to September is often seriously injured by am- 
brosia beetles. Heavy 2-inch to 3-inch stuff is also lable to attack 
by the same insects, even in loose piles. An example of this was 
found in some thousands of feet of mahogany lumber of the highest. 
grade, which had been sawed from imported round logs and /jpiled 
with lumber sticks between the tiers of plank. Native species of 
ambrosia beetles had entered the wood to such an extent as to have re- 
duced the value 50 per cent or more within a few weeks. Oak, poplar, 
gum, and similar woods often suffer severely from this class of injury, 
causing losses varying from 5 to 50 per cent. 
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 
[Cir. 128] 
