Excerpt from Larch Sawfly Conditions in the Lake States in 1954: A Reconnaissance Survey The extent and severity of the infestation in the Lake States in 1954 was determined by reconnaissance surveys similar to those made in 1953. In the northern half of Minnesota, an aerial survey was made to determine the areas of partial and complete defoliation. An intensive ground reconnaissance was also conducted in observation points established in 1951; data were taken on the amount of defoliation of individual trees, and cocoons were collected for research purposes. Because of the limited time available, only restricted ground observations were made in Michigan and Wisconsin where infestations are relatively light. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This 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.