ALLELOPATHY AS EXPRESSED BY SUGAR MAPLE ON YELLOW BIRCH

Abstract

This study involves investigation of alleged inhibitory effects of leachate from sugar maple (Acer saccharum Marsh., donor plant) on yellow birch (Betula alleganiensis Britton., vreceiver plant). The term allelopathy, introduced by Molisch in 1937 refers to this phenomenon in which one plant produces a chemical which inhibits the growth of another plant. The present investigation follows from that of Tubbs (1970) into competition between maple and birch for light and moisture. His results showed that there is a striking difference in birch growth between those grown in pure culture and those grown with maple, the latter being much lower. This reduced growth could not be accounted for by mere physical competition, and through further investigations, he was able to attribute some of this reduction in growth to allelopathic effects of maple leachate. Tubbs postulated that the active principle causing the inhibition was exuded from maple roots, that it was thermostable, water soluble and ephemeral.