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Show Will Wage War On Barkbeetles The latest modern method of fighting barbeetles by felling the in-sfeted in-sfeted trees and peeling off the bark, are to be used this spring in a great attempt to wipe out the barkbeetle menace which is now threatening' the two billion feet of timber on the Kai-bab Kai-bab National Forest, states R. II. Rutledge, District Forester, District 4, with headquarters at Ogden, Utah. Barkbeetles cannot be attacked in the same way as most destructive insects, in-sects, with poisonous sprays of one kind or another, as they spend most of their lives under the bark of trees, and prior to the great outbreak in the Black Hills 20 years ago, no feasible feas-ible method wsa known of the fighting fight-ing them. At that time, however, methods for destroying these beetles were devised, which have since been used with excellent results. These have been practised on a small scale upon the Kaibab Forest for the last two years, but have not been extensive exten-sive enough to do more than impede the barkbeetle advance. These beetles fortunately have fairly fair-ly regular habits. During the winter the eggs and young larva, or grubs, exist in the bark of the trees next to the wood. They stay there until well along in the spring when warm weather begins to bring them into activity and the grubs develop into adults. These adult beetles then fly to other live, unattacked trees, lay their eggs there, and thus extend the damage. The grubs living on the inner in-ner bark girdle and kill the tree. The object is to destroy the larva and insects in-sects before they mature and get out of the trees which they entered last fall. These trees can be easily distinguished dis-tinguished from healthy trees because the leaves begin to fade in the spring and there are also what is known as "pitch tubes" on the outside of the bark, as the pitch runs out through the hole where the beetle makes its entrance into the tree. Such trees as these which are dying and full of "pitch tubes" and full of beetle grubs and are cut down in the spring before be-fore the adult beetles begin to emerge. em-erge. The bark is carefully peeled off and turned over so that the part next to the wood lies exposed to the sun and drying influences of the wind and air. Under these circumstances, circum-stances, the immature beetles which are then, small, soft, white grubs, srivel up and die. In this way millions mil-lions of the insects can be disposed of at a very fair expenditure of money and the small number that are left, fall prey to their natural enemies, ene-mies, such as woodpeckers, other predatory beetles and even diseases which usually succeed in holding them in subjection. Such is the program of work that is mapped out in a general way for the coming spring onthe Kaibab National Na-tional Forest. It has to be done rapidly as the beetles come out by the millions along in early August, so that if they are caught in their immature im-mature stages, the work must be completed before that time. |