Collections: 
0-9 | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

Image 69 of Annual report. 1908

Part of Kentucky Agricultural Experiment Station

item | thumbnails | details | text | pdf
Download this image
y - 48 · Bulletin N0. 133. A A THE FIJAT-HEADED APPLE TREE BORER. ° (Ohrysobothris femomta). On the southwest sides of the trunks of apple trees the bark is i I sometimes found killed in a region just above the ground, and min- ing the bark of this region are one or more small white grubs with W a peculiar rounded and somewhat flat head region, for the flat part is not the head, but the body division just behind it. _The body is kept bent like the letter U, a feature by which this borer may be recognized from any other likely to be found working on . _ apple trees. i Q l The insect placing the egg is a gray beetle with metallic reflec— ~ tions, and somewhat flattened body. It will measure 0.44 to 0.48 x . inch in length. Adults emerge early in the spring and place their 4 eggs under the loose bark and in crevices anywhere from the ground ` up to the branches, and sometimes out on the bases of the latter. It appears to prefer the southwest sides of trees, but it is very prob- _— able that its prevalence here is due to the fact that the bark has been rendered defective by what is sometimes called sun—scald; the ‘ beetles prefer breaks of this sort as places to put their eggs. I suppose there can be no question that the insect prefers feeble trees, L; i but it seems equally certain that it helps in the destruction of trees it once attacked, since it is known to completely girdle the trunk in A I _ some cases. A common practice among apple growers is to go over the trees Q in the fall each year and cut out any borers that may have attacked ‘ _ them. Preparations of soap and other materials have been used to deter the beetles from laying their eggs on the trunks. They Y ¤ serve for a time, but must be renewed occasionally during the egg- laying season to be effective. A mixture of washing soda and soft .» soap has been highly recommended for the purpose. ‘ .· ` Sticky preparations such as Dendrolene are calculated to keep l A the adults away and have been tested to some extent for the purpose. A preparation called Tree Tanglefoot, somewhat like the material on sticky fly-paper has been tried by different entomologists and' " found harmless to the tree trunks, and very durable after exposure. by From my experience with such preparations for the Elm Leaf- beetle I am disposed to consider them valuable for insects attacking, ; I or creeping upon, the trunks. The substance is manufactured by