Injuries to Forests and Forest Products by Roundheaded Borers (Classic Reprint)

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Excerpt from Injuries to Forests and Forest Products by Roundheaded BorersThe work of this class of insects usually appears as irregular wind ing mines or wormholes f' in the bark and wood. The mine always starts in the bark, where the minute larva just hatched from the egg starts to bore and feed. At first the mine is very small, but gradually becomes larger as the borer advances and grows in size. As already indicated, the work of some species is confined entirely to the bark. The work of other species is found in both bark and wood. In this case the mine is continuous from bark to wood, the entrance into the wood being a ¿attened oval hole. That part of the mine which is in the wood may be long or short, according to the species. In general it is more or less winding and irregular, contains borings and woody exore ment, and finally broadens out into a cell or pupal chamber. At the farther end of this cell the mine, or exit burrow as it now becomes, usually leads directly to the surface by the shortest route. Upon the surface. It usually appears as a perfectly round exit hole (fig. 21, d)About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.