Antidesiccant Compounds Improve the Survival of Bare-root Deciduous Nursery Trees

Abstract

Desiccation stress during the postharvest handling of bare-root deciduous trees can account for dieback and poor regrowth after transplanting. Desiccation tolerance of three bare-root deciduous hardwood species was determined at monthly harvest intervals from Sept. 1990 through Apr. 1991. Among the three species tested red oak (Quercus rubra L.) was most tolerant to desiccation, followed by Norway maple (Acer platanoides L.) and Washington hawthorn (Crataegus phaenopyrum Medic.). Maximum desiccation tolerance of all three species occurred during the January and February harvests. Of 20 film-forming compounds tested, the antidesiccant Moisturin was the most effective in reducing water loss from bare-root trees during desiccation stress and in improving survival and plant performance during re-establishment in the laboratory, greenhouse, and field. Moisturin-treated plants lost up to 80% less water than untreated plants. Washington hawthorn seedlings treated with Moisturin before severe desiccating conditions had the highest survival, lowest dieback/plant, and highest root growth ratings. The results indicate that Moisturin is an effective means of overcoming postharvest desiccation stress in desiccation sensitive plants, such as Washington hawthorn.