Ethylene production in stem tissues of red-osier dogwood (Cornus sericea L.) following heat treatment was determined at several growth stages. Ethylene production of heat-stressed stem tissue depended on the stage of development and was a function of the degree of stress. During active growth and early endodormancy, heat stress of stem tissues stimulated ethylene production, reaching a peak at 40C, followed by a steady decrease at higher temperatures. Highest ethylene levels from stressed tissues occurred in May, July, September, and March. Only a trace amount of ethylene was produced during endodormancy to ecodormancy (late October to January) from stressed and nonstressed stem tissues. Applying ACC to stem segments at late endodormancy (December) or applying methionine and IAA to stem segments at maximum endodormancy (November) enhanced ethylene production of both nonstressed and heat-stressed stem tissues. Chemical names used: 1 H- indole-3-acetic acid (IAA); 1-aminocyclopropane-1-carboxylic acid (ACC).