HOW TO COMBAT THE ATTACK OF INJURIOUS FOREST INSECTS. 17 
Wurtemberg, in 1872, about 231,000,000 cockchafers were 
gathered and destroyed. 
Dead cockebafers have been put to the most varied uses. They 
have been proved to furnish first-class food for pigs and poultry, 
they form an excellent manure, and have also been employed in 
the manufacture of waggon grease and printing ink ; and a silver- 
amalgam work near Freiberg was for several years lighted with 
gas obtained from the dry distillation of cockchafers, 
The pine weevil is often captured in large numbers by hand- 
picking. This can be performed by children, who in early summer 
search the woods formed during the previous winter. The cap- 
tured insects are best placed in small bags, the mouth of each 
being furnished with a bottle-neck to prevent them finding their 
way out easily. 
Another method of catching pine weevils has many advocates, 
It is, however, only applicable to cases where the surface is fairly 
level, and the soil firm but not very stony. The modus operandi 
is as follows :—When a coniferous wood has been felled during 
winter, the area is, immediately after the removal of the trees, 
surrounded with a trench 10 to 12 inches broad and as many deep. 
The sides must be perpendicular, and as smooth as possible. At 
intervals of ten paces or so there are constructed, in the bottom of 
the trench, special pitfalls, 4 to 8 inches deep, These trenches 
must be visited every few days, and the captured beetles destroyed. 
As the trenches are apt to become damaged or silted up during 
heavy rains, they must be frequently examined, and, if necessary, 
repaired. The object of this method is the capture of all pine 
weevils which are making towards the fresh stools on which to 
deposit their eggs, as well as those which have been hatched there, 
and are proceeding to the adjoining young woods to prey on the 
trees. The system is largely employed in many parts of Europe, 
and where the conditions are favourable, it is both cheap and 
efficacious. In the trenches are captured not only pine weevils, 
but also other destructive weevils and insects generally, which are 
incapable of or averse to flight. 
The preventive measure employed in the case of the winter moth, 
Cheimatobia brumata, at present devastating the orchards in the 
west of England, falls under this heading. As is well known, the 
imago stage of this insect is attained under the earth, after which 
the wingless females proceed to crawl up the stems of fruit and 
other broad-leaved trees for the purpose of depositing their eggs in 
VOL. XIII, PART I. B 
