REDUCING DROUGHT STRESS IN TRANSPLANTED TREES USING MYCORRHIZAE^©

High mortality rates among most species of nursery trees after transplanting is generally attributed to water stress imposed by a range of soil and other environmental conditions. This study examined the efficacy of a consortium of mycorrhizae (Root Rescue Landscape Powder), comprised of 20 species of both endo- and ecto-mycorrhizae, in mitigating water stress when inoculated into the root zone of recently transplanted trees [Thuja occidentalis ‘Smaragd’ (emerald pyramidal cedar) and Acer rubrum ‘Brandywine’ (Brandywine red maple)]. The water status of the trees was monitored with automated stem psychrometers measuring stem water potential (Ψ) at 30-min intervals for at least 2 weeks after transplanting. Treated trees exhibited a significant reduction in mid-day water stress and enhancement of overnight rehydration, relative to control trees, when inoculated with the consortium of mycorrhizae, as shown by diurnal patterns of water stress and recovery.