Reproductive and seedling ecology of a semelparous native bamboo (Arundinaria gigantea, Poaceae)

GAGNON, P. R. AND W. J. PLATT (Louisiana State University, Department of Biological Sciences, 202 Life Sciences Building, Baton Rouge LA 70803). Reproductive and seedling ecology of a semelparous native bamboo (Arundinaria gigantea, Poaceae). J. Torrey Bot. Soc. 135: 309–316. 2008.—Canebrakes were monodominant stands of bamboo once common in bottomlands throughout the southeastern U.S. They were habitat for many wildlife species, and have declined drastically since the 18 century. Knowledge of the reproduction of canebrake bamboos is sparse and often contradictory. We studied reproduction and the role of disturbance in one canebrake bamboo, Arundinaria gigantea (Walt.) Muhl., at two field sites in Louisiana. We noted flowering with little or no seed-set during each of four years at our primary study site, and a massflowering event at a second site from which we collected 2,000 seeds. Of these, 82–95% proved viable in germination trials. We used these seeds in a 2 3 2 factorial design at the Buckhorn Wildlife Management Area in NE Louisiana to test the effects of prior windstorm and fire on seed germination and seedling survival. Results indicate that A. gigantea is capable of reproducing in the leaf litter and partial shade typical of open forest habitat but may have problems reproducing in burned-over areas with bare mineral soil. We identified three potential bottlenecks in the species’ regeneration and proposed that successful outcrossing may drive synchronized flowering events in these and other bamboos. We presented implications for canebrake restoration efforts, plus several questions that might be examined by future studies.