||Cold-moist stratification for 60 days and incubation at 30 degrees C resulted in significantly higher percent germination than did storage of seeds at room temperature or cold-dry stratification and/or incubation at cooler temperatures. The indurate cupule that surrounds the caryopsis reduced or inhibited germination, depending upon seed source, but this inhibitory effect was reduced by providing the seed with cold-moist stratification and incubation at 30 degrees C. Mechanisms for this inhibitory effect of the cupule were examined.this included testing for release of inhibitory chemicals by the cupule and examining germination at ambient and enriched levels of CO2 (5%) to determine if enhanced levels of CO2 that might incur inside the cupule as a result of embryonic respiration, could inhibit germination. No evidence was found which supported either of these hypotheses. The cupule may play a role in seed dispersal by protecting the seeds as they pass through the digestive tracts of potential dispersal organisms. Six days after 500 cupules were fed to cow, 51 intact caryopses passed through the animal’s digestive tracts and some of these retrieved seeds germinated. The cupule also protects the caryopsis from some forms of predation once it becomes indurate, especially chewing insects. However, in the field 95% of the annual fruit production was preyed upon by small rodents that gnaw through the cupule. A fungal-inhibiting Pseudomonas bacteria was routinely isolated from the caryopses of some populations of eastern gamagrass and it may play some role in protecting the seeds from attack by fungal pathogens.