A report on four rare plant species of Big Bend National Park, Texas

Big Bend National Park in Texas serves as a refuge for many rare plant species, many of which can be found nowhere else in the United States. This study is a summary and synthesis of the available research that has been done on four rare plants in Big Bend National Park: Coryphantha ramillosa subspecies ramillosa (bunched cory cactus), Echinocereus chisoensis var. chisoensis (Chisos Mountain hedgehog cactus), Echinomastus mariposensis (Lloyd’s mariposa cactus), and Festuca ligulata (Guadalupe fescue). The objectives of this study were (1) to review and synthesize all existing published and unpublished studies of these species, with a focus on known threats, conservation priorities, and research needs, (2) to create a GIS database of available public and private data relevant to these species, and (3) using this database, to conduct a preliminary analysis identify the primary habitat characteristics of each of these species at both local and landscape scales. At the landscape scale, geological substrate, elevation, and topographic position characterized species' habitats. At a local scale, slope and sometimes soil unit determined species presence. Further research is needed on each species. Each of these species faces multiple threats, and collaborations between government agencies, private conservation organizations, private landowners, and researchers may be essential to the recovery of these species.