"20 THE WESTERN HEMLOCK. 



The danoer is lessened ))y thick hurk. which renders it ditticult for the 

 insects to enter. For the same reason large trees are safer than small 

 ones. The}' are frequently streaked near the center, but not toward 

 the outside, showing- that when the tree reached a certain size its bark 

 became thick enough to protect it. (PL VII, tig. 1.) As yet protec- 

 tive measures against this insect are unknown, but much disappoint- 

 ment might be prevented b}^ an examination of standing timber for 

 traces of the insects. It is useless for manufacturers of cooper stock 

 or finishing lumber to bu}' infected logs. The presence of the larva 

 in the standing tree is always apparent to a close observer. 



IMMUNITY FROM WHITE ANTS (tERMITES). 



Experiments made in Manila indicate that Hemlock may prove of 

 special value in tropical countries where most woods are destroj^ed b}^ 

 ants. Capt. George P. Ahern, chief of the Philippine forestry bureau, 

 states in a recent report that the master mechanic of the depot quarter- 

 master's shops, Mr. D. N. McChesney, tested several American woods 

 by thirty da^'s' exposure to the attack of ants with the following 

 results: 



Oregon Pine (Red Fir) Entered and eaten; a mere matter of time for complete 



destruction. 

 Bull Pine ^ 



Eaten more readily than Oregon Pine. 



Spruce . . /■ 



California Redwood . . . -. . , , , . . , . 



California White Cedar [ - ^^"^^ ^'''''^' ^'"^ 'li^contumed alter .light effort. 



Hemlock Not touched. 



Further experiment is now being made. Since the depredations of 

 ants are of great importance, not only in the Philippines but in other 

 tropical countries, a wood which will withstand them is certain of a 

 good market. Although Cedar and Redwood have the reputation 

 of being ant proof, they are not adapted to manv uses for which 

 Hemlock is excellent. 



For many 3'ears farmers have used Hemlock for the construction of 

 oat bins and similar receptacles designed to be rat and mouse proof. 

 It is said that the wood is distasteful to all rodents. 



A parasite {Arceuthohium occidentale) resembling mistletoe is wide- 

 spread throughout the Hemlock region. It grows upon the branches 

 and leading shoots, causing distortions and occasionalh' death. When 

 the branches only are attacked, the result is a disturbance of their 

 functions, and consequently a slow, sickly growth of the tree, which, 

 however, does not affect the quality of the timber. If, however, the 

 plant gets foothold on the leading shoot, a burl follows which persists 



