Silvics of Forest Trees of the United States Agriculture Handbook No. 271 FOREST SERVICE U.S. DEPARTMENT OF AGRICULTURE SILVICS OF FOREST TREES OF THE UNITED STATES Prepared by the Division of Timber Management Research Compiled and revised by H. A. FOWELLS Chief, Branch of Silviculture Agriculture Handbook No. 271 U.S. DEPARTMENT OF AGRICULTURE FOREST SERVICE 1965 Library of Congress Catalog Card Number: Agr 65-273. For sale by the Superintendent of Documents, U.S. Government Printing Office i 1 FOREWORD For several decades forestry scientists in the United States have faced the major challenge of identifying and classifying the several hundred tree species found in our Nation's forests and of learning their life histories and requirements. It was necessary to do this because of the basic importance of such information to the proper development of silvicultural systems and related cultural methods for American forests. Substantial progress has been made in the identification of trees. Dendrological research, except for refinements and details, has largely been completed. Results of the research are recorded in many volumes, among which the Forest Service's "Check List of Native and Naturalized Trees of the United States" is the most recent contribution. Less progress has been made in studying the life histories of trees and determining their responses to the environment. However, a large quantity of such information has been accumulating from the researches of the Forest Service, universities, industry, and others. Attempts to bring this silvical information together are relatively recent. The "Woody-Plant Seed Manual" represents the first comprehensive summary of this nature by the Forest Service. It was published in 1948 as U.S.D.A. Miscellaneous Publication 654, and is still the standard reference work on seeds of forest trees of the United States. This handbook is the second comprehensive summary of silvical information on American forest trees by the Forest Service. It is an edited compendium of nearly 125 silvical leaflets prepared by specialists at the Forest Service experiment stations. Most of these leaflets, each covering a single species, were published by the Stations as they were completed. This handbook should be most useful to research organizations and universities for research and training purposes. We believe it will provide a ready reference in the university classroom and laboratory and will be an important source of knowledge for silvicultural research. It should also prove helpful to the practicing forester. ぱな V. L. HARPER, Deputy Chief In Charge of Research Forest Service ш |