Abstract | We exposed seven species of plant seeds to aqueous extracts of Creosotebush leaves: Black Grama, Bouteloua eriopoda; Sideoats Grama, B. curtipendula; Burrograss, Scleropogon brevifolous; Fluffgrass, Dasyochloa pulchella; Bush Muhly, Muhlenbergia porteri; Tarbush, Fluorensia cernua; and, Creosotebush, Larrea tridentata. We also included lettuce as a standard bioassay for allelopathic effects. Extract concentrations varied from 0 to 50 times th concentration found in stemflow during a typical summer rainfall event. Germination and radicle elongation of plant species closely associated with Creosotebush were affected differently than those whose populations are reduced with increasing Creosotebush density. |