Seed ecology of Lindera melissifolia (Lauraceae) as it relates to rarity of the species
The seed ecology of the federally endangered shrub, Lindera melissifolia was investigated to determine if this aspect of the species life history contributes to the rarity of the species. Lindera melissifolia has the capacity to form a short-lived (two growing seasons) persistent soil seed bank if fruit pulp remains on seeds following dispersal and subsequent winter flooding occurs. Seeds, both with or without pulp (i.e., mesocarp and exocarp), exhibited tolerance to submergence, but were not hydrochorous. Following 6–12 weeks cold stratification (5u or 5/1u C) or submersion in cold water (5/1u C) for 12 weeks, $ 63% of seeds germinated when incubated in light and at temperatures of 35/20u and 30/20u C. When incubated in darkness, 100% of seeds germinated following 6 weeks of cold stratification. Giberrelic acid was moderately effective in breaking dormancy. Collectively, our results indicate that seeds of L. melissifolia have nondeep physiological dormancy. Aspects of the seed ecology of L. melissifolia that may contribute to continued rarity of the species include absence of a longterm persistent soil seed bank, no obvious mechanism of long-distance dispersal, and late season germination that prevents seedling growth to a sufficient size for survival prior to cold temperatures and flooding.