Population Ecology Study of Epifagus virginiana (L.) W.P.C. Barton (Beechdrops) in Central Indiana

Abstract

Epifagus virginiana (Beechdrops) is a holoparasitic plant that is obligate on the roots of Fagus grandifolia (American Beech) throughout mesic forests in the Midwest. This parasite has a coefficient of conservatism of 8, indicating it requires high-quality plant communities and tolerates little disturbance. Epifagus virginiana resembles twigs, producing inconspicuous flowers from August to October. An unexpectedly large population of this species, comprised of 886 plants growing on 17 F. grandifolia trees, was found in Hougham Woods Biological Field Station (HWBFS) in Johnson County, Indiana. Plants were morphologically similar to descriptions in literature, with an average height of 16.1 cm and many were commonly observed growing in association with large Fagus grandifolia trees (DBH . 40 cm). A statistic previously undocumented was that these plants had cleistogamous and chasmogamous flowers in a 20:1 ratio. Chasmogamous flowers in this population proved sterile. However, since each cleistogamous flower produced an average of 827 seeds, the E. virginiana population in HWBFS displays a very large reproductive potential for the coming years. Monitoring this population could provide a way to assess the health of this forest
remnant.