RESOURCES FOR THE FUTURE, INC.
1755 Massachusetts Avenue, N.W., Washington, D.C. 20036

Board of Directors:
Erwin D. Canham, Chairman, Robert O. Anderson, Harrison Brown, Edward J. Cleary,
Joseph L. Fisher, Luther H. Foster, F. Kenneth Hare, Charles J. Hitch, Charles F.
Luce, Frank Pace, Jr., Emanuel R. Piore, Stanley H. Ruttenberg, Lauren K. Soth,
Maurice F. Strong, Mrs. Robert J. Stuart, P. F. Watzek, Gilbert F. White.

Honorary Directors: Horace M. Albright, Reuben G. Gustavson, Hugh L. Keenleyside,
Edward S. Mason, William S. Paley, Laurance S. Rockefeller, John W. Vanderwilt.

President: Joseph L. Fisher
Secretary-Treasurer: John E. Herbert

Resources for the Future is a nonprofit corporation for research and education in the
development, conservation, and use of natural resources and the improvement of the
quality of the environment. It was established in 1952 with the cooperation of the Ford
Foundation. Part of the work of Resources for the Future is carried out by its resident
staff; part is supported by grants to universities and other nonprofit organizations.
Unless otherwise stated, interpretations and conclusions in RFF publications are those
of the authors; the organization takes responsibility for the selection of significant sub-
jects for study, the competence of the researchers, and their freedom of inquiry.

This book is one of RFF's studies in land use and management, which are directed by
Marion Clawson. The illustrations were drawn by Frank J. Ford and Clare Ford. The
index was prepared by Helen Eisenhart.

RFF editors: Mark Reinsberg, Vera W. Dodds, Nora E. Roots.

Copyright © 1973 by The Johns Hopkins University Press
All rights reserved
Manufactured in the United States of America

The Johns Hopkins University Press, Baltimore, Maryland 21218
The Johns Hopkins University Press Ltd., London

Library of Congress Catalog Card Number 72-12364
ISBN 8018-1496-0

Library of Congress Cataloging in Publication data will be found on the last
printed page of this book.

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