Conservation of Texas Prairie Dawn, Hymenoxys texana (Asteraceae), and Neche’s River Rose-Mallow, Hibiscus dasycalyx (Malvaceae), by Mercer Botanic Gardens

Mercer Botanic Gardens, a Harris County botanical park facility, began endangered native plant conservation efforts in 1986 with the ex-situ conservation (seed banking and propagation) of a local federally listed species, Texas prairie dawn, Hymenoxys texana, Asteraceae (G2) and its rare saline prairie associates. Mercer became a participating institution for the Center for Plant Conservation (CPC) in 1989 and became a lead botanic institution for the conservation of rare native East Texas and Upper Gulf Coast species. In 1992, Mercer began ex-situ conservation efforts for Neches River rose-mallow, Hibiscus dasycalyx, a rare (G1) East Texas wetland shrub. H. dasycalyx reached federal candidate status in 1996 and became listed as a threatened species in 2013. Although seed banking and public outreach are a primary focus of Mercer’s rare native plant conservation efforts, in situ conservation efforts expanded as the botanic gardens became primary advisor (2005) and manager (2013) for a naturally occurring population of H. texana at the Harris County Prairie Dawn Preserve. An update of conservation efforts by Mercer for H. texana and H. dasycalyx will be presented.