20 
EVIDENCE OF THE WORK OF THE BEETLE ON OLD DEAD TREES. 
After the trees have been dead many years most of them decay at 
the base and fall, while the main trunks or snags of others remain 
standing; yet as long as the surface of the wood remains sound the 
characteristic longitudinal gallery grooves will be more or less distinct, 
and serve to indicate that the trees were attacked while living. Pieces 
of the old bark will also usually show traces of the galleries and indi- 
sate by the pitch-preserved tissue that the galleries were excavated in 
living bark. Traces of the pitch tubes may also remain on the outer 
bark for many years and serve to indicate the cause of the trouble. 
RELATION OF WOOD-BORING INSECTS AND WOOD-DESTROYING 
FUNGI TO THE RAPID DETERIORATION OF THE WOOD. 
As previously indicated, there are a number of wood-boring insects 
which bore into the sapwood of dying and dead trees. Some also 
penetrate the heartwood. Some of these wood-infesting insects enter 
tne wood as soon as the tree commences to die, others after it is dead, 
and still others at different stages of the decline and decay as long as 
there is anything left for them to work in. It is only those, however, 
that enter the wood while it is yet of value for commercial purposes 
that need to be specially mentioned in this connection. Next to the 
one that makes the primary attack, those borers which enter the sound 
wood are probably of the greatest importance. They not only cause 
pin-hole and wormhole defects, which depreciate the value of the lum- 
ber and other products into which the wood of the dying and dead 
trees may be converted, but they give entrance to wood-decaying fungi, 
causing rapid decay of the wood of the standing trees which would 
otherwise remain sound for a much longer period. 
While the injuries by these wood-boring insects are by no means as 
common where there are a great many dead and dying trees as where 
there are only a few, it was found to be suflicient in some sections to 
‘ause, in connection with the wood-decaying fungi, a worthless condi- 
tion of the timber over large areas. Indeed, it would seem from such 
observations as we were able to make that unless the trees are cut 
and converted into lumber, ties, cordwood, or other commercial prod- 
ucts within two or three years after they commence to die, very little 
of value is left. 
SUGGESTIONS FOR PREVENTING LOSSES. 
The limited time devoted to the study of this new insect was not 
sufficient to determine the details in its life history and habits which 
are usually so necessary in the consideration of remedies, but some 
general features were noted, which, in connection with the information 
acquired from special investigations of the closely related destructive 
