Seasonal timing of corm development in Erythronium americanum

Abstract

Our collective knowledge of the natural history traits of our native species is commonly lacking, and this deficit puts us at a disadvantage as we try to predict responses of species, communities, and ecosystems to current, widespread environmental changes wrought by human activities. Erythronium americanum Ker Gawler is a common spring ephemeral in the forests of the eastern United States and it plays an important role in biogeochemical cycling and food webs. Yet, there remain unresolved questions about its developmental patterns and therefore capacity to respond to environmental change. In this study, I collected 30 corms with no roots that had recently formed from droppers and 30 older corms in the spring, replanted them adjacent to Plexiglas for viewing, and monitored their development semi-annually for two years. Older corms produced a second set of roots during the summer. Young corms formed roots during the first summer of their existence. Both old and new corms only formed droppers in the spring following transplanting. Not all second year corms produced droppers. Corms that formed droppers did not persist when a new corm was formed at the end of the dropper. These results indicate that Erythronium americanum faces a delay in its response to environmental changes, and not all young corms respond significantly within two years even though most young corms can form droppers.