Abstract

Kozlowski, T.T. 1976. Susceptibility of young tree seedlings to environmental stresses. American Nurseryman 144(12): 12-13, 55-59.

Young seedlings of woody plants generally grow at threshold levels of physiological growth requirements. After a young seedling depletes reserve foods contained in the seed, its growth depends on food synthesized by cotyledons or synthesized by the first true leaves. Such young seedlings are very susceptible to such environmental stresses as low light intensity, drought, low or high temperatures, air pollutants, and various applied chemicals, including some insecticides, fungicides, and herbicides. Harmful effects of chemicals may include growth inhibition, abnormal seedling development (e.g., curling, shriveling, and fusion of cotyledons; chlorosis, and distortion of seedlings) and killing of seedlings. For these reasons, young seedlings in the cotyledon stage of development require intensive care to avoid even temporary unsuitable environmental conditions.

• © 1977, International Society of Arboriculture. All rights reserved.