208 REPORT OF THE DEPARTMENT OF ENTOMOLOGY OF THE- 
FEEDING HABITS OF THE ADULT. 
The adult is a voracious eater and obtains subsistence by 
puncturing the bark and feeding on the cambium layer. For the 
first week or ten days after emerging the beetle feeds extensively 
upon the tender bark of one year old branches, then copulation 
takes place, after which the beetles are more often found on the 
older parts of the tree. One observation seems to indicate that 
young bark is a prime necessity. A number of beetles developed 
in a breeding cage in which there was only the old wood from 
which they had emerged. The beetles did not eat the old bark 
and many appeared dead after three or four days, but revived 
when put on a diet of young twigs. This was probably the 
ripening period for oviposition, as during the first week or ten 
days after emerging no eggs are deposited. When the beetles 
are ovipositing they are more often found puncturing the bark 
of two to four year old wood, and if at this time they are given 
twigs and small branches of one year old wood exclusively for 
food, they will riddle the bark with punctures but will not 
Oviposit in the bark. In several instances similar to this the 
eggs have been deposited on the floor or walls of the breeding 
cage. No eggs have been detected in the bark of one year old 
wood. This apparent distinction shown by the beetle between 
one year and two year bark is brought out strongly in one of 
the methods of growing poplars in the nursery, which is as 
follows: A cutting of one year wood is put in the ground. This 
is allowed to root and one bud to grow. After one year’s growth 
the shoot and tap root are pruned and the stock replanted. At 
the end of another year it is called a one year old tree, though it 
may have six or eight inches of two year wood above ground. 
These one year trees are often infested but the point where the 
eggs are inserted will invariably be in the two year old wood. 
According to nurserymen, this pruning and replanting is done to 
give the tree a better root system. 
DISTANCE THE BEETLES TRAVEL TO FIND NEW, PASTURES. 
In infested localities the beetles seem to be present everywhere 
upon willows and poplars, and it is evident that they occasionally 
migrate or are scattered by some means. ‘However, none have ever \ 
been observed in the act of migration. The beetles have perfect 
wings but in the observations of two summers none have been seen 
flying. In a grove composed mostly of poplars and willows, some 
