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Show ROUNDHEADED APPLE TREE BORER PEST Clump of Service Bushes Showing Exit Holes of Roundheaded Apple-Tree Borers. (Prepared by the United States Department Depart-ment of Agriculture.) The roundheaded apple-tree borer, the most destructive of a number of similar pests, causeB much damage to apple orchards in the eastern hall of the United States. It does not confine Its destructive methods solely to apple trees, but feeds on other fruit trees, as well as service, wild crab and mountain ash. which makes it advisable to cut out these latter varieties for a distance of at least a hundred yards from the orchard. The presence of the borers Is easily detected. Sawdustlike castings of a reddish color are thrown out through small holes in the bark as the borers feed Heaps of these castings found at the base of apple, pear or quince trees are always an evidence that the trees need immediate attention. Fre quently an examination of an orchard Induced by finding one tree with cast ings at the base will reveal the fact that many trees are affected and that serious injury has already been done Ordinarily the parent beetle lives about 40 or 50 days. It is about three fourths of an Inch in length, light brown in color above, with two broad white bands Joined in front, extending the full length of the back; the un derparts and front of the head are white. The females rarely fly any considerable distance, so that if the immediate vicinity of an orchard can be kept free from them, there is little danger of a serious Infestation. Worming to Be Thoroufjhly Done. The most common method of ridding rid-ding an orchard of these pests Is to cut away the bark sufficiently to trace the burrows made by the borer. A hooked wire is then inserted into the burrow and the insect pulled out. If made with caie. the wound In the tree caused by this process will heal readily. The castings at the base of the tree serve as an indication of tbo presence of the borers. Where the burrows are curved or obstructed in some way so that the wire cannot br-inserted, br-inserted, cotton batting dipped in cat bon bisulphid should be Inserted and the hole then plugged with moist earth. The gas from the carbon bi sulphld will penetrate all parts of the burrow and kill the borer. In exten sive orchards where worming Is done on a large scale by promiscuous labor some of the helpers are likely to become be-come careless and overlook or neglect to destroy an occasional borer. Every female so overlooked stands a good chance of maturing within a year or two. when it will deposit eggs in a half dozen or more nearby trees, causing caus-ing thereby a continued and an increased in-creased infestation in that particular orchard. The Importance of the following points should be kept in mind by all persons who practice this method of borer control: 1. Borers should be removed from the trees as soon as possible after hatching. 2. Every borer in tbe orchard should be found and destroyed. 3. Borers should not be allowed to breed in cultivated or wild host trees growing within at least 200 or 300 feet of the orchard. Paint Acts as Preventive. In addition to worming, as this process is called, paint is often used to prevent the beetles laying their eggs Pure white lead and raw lin seed oil. mixed rather thick, will not Injure the trees, and when applied to young, smooth bark, will form a pro tective coat during the egg laying sea son. It Is probable that this is a more effective method than wrapping the trees with building paper, cotton bai ling, cloth or other materials some times used for this purpose Before painting, howevei. the earth should be removed from the base of the tree for a depth ol from three to four Inches The surface of tbe trunk thus exposed should be first scraped and painted and the earth then replaced. This Is necessary, for the beetle occasionally lays her eggs under instead of above the ground As the Insect in Its borer'stage lives and feeds under the bark, insecticide sprays cannot be used successfully against it. When the borer has reached the adult stage It feeds more or less on the exposed surface of leaves and twigs and on the moisture contained in the fresh castings thrown out by, borers still working in the trees Arsenate of lead sprayed on trees on which they are feeding would kill many of the adult beetles, but It Is doubtful If it would pay ordinarily to spray lor the purpose of killing this insect alone, except in the case of a badly Infested orchard Farmers' bulletin No C75, "The Roundheaded Apple-Tree Borer,' which contains a description of this pest and different methods of control may be secured upon application to the United States department of agriculture. |