The allelopathic influence of post oak (Quercus stellata) on plant species in southern U.SThis article is part of a larger document. View the larger document here.
Post oak (Quercus stellata) is a commonly occurring tree in the southeastern United States, offering forage and shelter for a variety of wildlife as well as having commercial uses. This species is often planted in parks and urban green-spaces for the shade it offers. Previous studies have found that parts of the plant can be toxic to livestock and that it can inhibit the germination and/or growth of plant species in its vicinity. This study focuses on the allelopathic potential of post oak in an urban, old growth forest. Post oak was selected subsequent to an understory inventory of plant species on a plot established in Marshall Forest in Rome, GA. White oak (Quercus alba) and chestnut oak (Quercus montana) seeds, and muscadine (Vitis rotundifolia) were used to determine if leachates prepared from leaves collected from Post oak inhibit germination and/or growth. Radish (Raphanus sativus) was also used, as it was previously found to be impacted by post oak. Two different concentrations of leachate were prepared and tested on the selected species. The results revealed significant differences in both germination rates and mean sprout lengths between the control (distilled water) and both concentration groups. No significant difference was found between the two concentrations of leaf leachate during the experiment. These results suggest that post oak inhibits the germination rate and sprout length of the tested species. It is important that resourcemanagers understand these relationships in managed landscapes (e.g., parks). In the future, it may be possible to utilize allelochemicals from post oak as a biocontrol agent.