. An annotated list of the important North American forest insects. Forest insects. Biology and Control of the White-Pine Weevil ii seldom been observed in flight. (Jnly once in the course of these investiga- tions has it been observed on the wing. This one occasion was in mid- afternoon of a warm day in the early spring of 1916. On that day, many weevils were fl>^ng. They were strong fliers, and when in the air their movements were similar to those of such bark beetles as Hylurgops. This unusual occurrence suggests the possibility of a short period of flight during earlv spring, whereby th
. An annotated list of the important North American forest insects. Forest insects. Biology and Control of the White-Pine Weevil ii seldom been observed in flight. (Jnly once in the course of these investiga- tions has it been observed on the wing. This one occasion was in mid- afternoon of a warm day in the early spring of 1916. On that day, many weevils were fl>^ng. They were strong fliers, and when in the air their movements were similar to those of such bark beetles as Hylurgops. This unusual occurrence suggests the possibility of a short period of flight during earlv spring, whereby the weevil becomes widely disseminated, followed by a period when it seldom if ever takes Figure 5. adult white-pine weevil During the spring of 1916 an experiment was conducted to determine, if possible, how the adult weevils reach the leading terminal. Two bands of tree tanglefoot, one just above the ground and the other at the base of the leading shoot, were placed around the stems of forty trees in a stand of young white pine that had been heavily infested by the weevil in 1915. These bands were applied just before the adults began to emerge from hibernation. As soon as the weevils began to emerge, about two hundred were collected and liberated on the ground in the center of the plot. This number of weevils, added to the nurnber already present, insured a heavy infestation. With this arrangement of tanglefoot bands, it was certain that any weevils found on the terminal of a banded tree had not crawled up the tree. Any that were caught in the upper band must have alighted on a side branch, and any that were caught in or found below the lower band must have crawled up from the ground. During the entire season, no weevils were caught in any of the bands. Many weevils, however, were. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly
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Keywords: ., bookauthorhopkinsadandrewdelmar, bookcentury1900, bookdecade1900
