il ' ii - Northern Research Station - USDA Forest Service

PREFACE
This proceedings is the result of an international symposium that was held August 14-19, 1997 in M_itrafiared, D *
Hungary. It was organized under the guidlines of the International Union of Forestry Research Organizations (IUFRO)
by the Hungarian Forest Research Institute, Department of Forest Protection, and the North Central Research Sta-
_tion of the U.S. Forest Service. IUFRO Working Party $7.03-02 (Gall-forming Insects) and Subject Group $7.01-00
(physiology and Genetics of Plant-herbivore Interaction) convened for this conference.
The proceedings is published and distributed by the USDA Forest Service, North Central Research Station in recognition
of and unstinting endorsement of the IUFRO goals of promoting strong world partnerships, particularly in
forest science, for the sustained management, conservation, and betterment of the World's forests and woodland
ecosystems.
ACKNOWLEDGEMENTS
The editors gratefully acknowledge the crucial support of the Hungarian Forest Research Institute, the Forest De-
. partment of the Hungarian Ministry of Agriculture, and the private companies Agroinform Publishing House, InterDnet,
and Matra Forest and Wood Company for underwriting the costs of organizing the symposium, and the North Central
Research Station for assembling, editing, printing, and distributing this publication. Finally, the editors also
wish to thank aH of the participants whose spirited contributions helped make this scientific exchange so worthwhile
and extraordinary.
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