Trap trees and trap logs are sometimes effective in the control 
of bark beetles (552). Bands of tanglefoot or similar materials 
may be placed around the trunks of shade trees to prevent larvae 
or wingless female adults of several species, such as the fall 
cankerworm, from ascending the trees to feed or oviposit. Young, 
newly-planted shade trees may be protected from borers of 
various kinds by enclosing the trunks in wrapping paper. Bag- 
worms on ornamental trees may be controlled by handpicking. 
Subterranean termites can be kept out of structures by capping 
foundations with a 4-inch layer of high grade concrete or with 
properly applied metal shields, by keeping untreated wood from 
contact with the ground, by using solid foundation masonry, and 
by providing good ventilation between the ground and timbers. 
The logging and milling of infested timber and destruction of 
the slabs containing the broods is often effective in preventing 
bark beetle outbreaks, but this may be feasible only where the 
trees are of merchantable size, are accessible, and when they can 
be harvested promptly. Bark beetle broods in or under the bark 
may also be disposed of by the storage of infested logs in water ; 
by peeling infested logs and burning the bark; by sawing infested 
trees into short lengths and burning them; by peeling the bark of 
infested trees and exposing the brood to desiccation and to natural 
enemies such as ants, birds, and rodents; or by felling infested 
trees in a north-south direction in the open where the bark is 
exposed to heat from direct exposure in the sun. 
Ambrosia beetle damage to summer cut logs can be reduced or 
prevented by the quick removal of the logs from the woods, by 
quickly manufacturing them or storing them in ponds, by quickly 
drying the lumber cut from them, and by the removal of the bark 
from rough-hewn pieces. 
Ips bark beetle populations which develop in slash following 
cutting operations can be reduced by limiting small scale cuttings 
to the fall and winter months, or by continuing large scale cut- 
tings throughout the summer months. In situations where it is 
necessary to cut on a small seale or discontinuously during the 
summer, control may be obtained by piling and burning the slash 
before the beetles complete their development in it. The gathering 
and burning of severed branches late in the fall or in the winter 
or early spring when the eggs and grubs are in the twigs is an 
effective method of controlling twig girdling species. 
Wood-borer damage to field-piled pulpwood in the Lake States 
has been reduced by piling the wood in the shade or by placing it 
in standard compact piles. Lyctus powder-post beetle damage can 
be reduced by the long storage of susceptible sapwood in water or 
by steaming it at high temperatures. Bark-beetle damage to bark- 
covered poles and slabs used in rustic construction can be reduced 
or prevented by cutting the material during the fall and winter 
and then seasoning it off the ground and under cover. Damage to 
young pines by the European pine shoot moth in the Lake States 
can be reduced by removing the lower limbs. This forces the over- 
wintering stages of the insect into buds on the upper branches 
above the snow line where they are killed by lethal low tempera- 
tures during the winter. 
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