June 30

Abstract

June 30, 2006 No. 15 They come in all shapes and sizes................... Galls are abnormal growths of plant tissue caused by various organisms. The exact mechanism causing gall formation is not known, but is thought to be a plant response to hormonal substances introduced mainly by various species of insects and mites. Some of the gall forming organisms include gall flies, gall wasps and some of aphids, adelgids and phylloxerans. Many species of eriophyid mites cause a multitude of strange appearing deformities.