Carex austromexicana

Forests of the Sierra Madre of Oaxaca have remained relatively intact, despite human exploitation, due to the extremely abrupt and rugged topography. The main threats to plant species in the region is the loss of habitat due to agriculture and cattle farming which facilitate erosion and soil loss, and thus hinders the ability of these pine-oak forests to regenerate. Collection of plants with ornamental value and uncontrolled resin extraction of pine trees are other threats (Valero et al. 2001). This species appears to be resilient to fires and may even benefit from it. It was still found at the type locality after a fire destroyed most of the pines, some years ago. However, as with any newly opened areas in Mexico, the type locality is now pressured by heavy grazing. In 1997, it was still extant at the type locality but badly overgrazed. This distinctive local endemic is endangered by habitat degradation (A. Reznicek pers. comm. 2009). Small sized isolated populations of clonal species are likely to have a small genetic variability and are particularly subject to inbreeding and genetic drift and to demographic and environmental stochasticity (Wolf and Konings 2001).

The Sierra de Juàrez montane forests are characterized by high plant endemism, a high number of endangered plant species and uniqueness of the floral composition, and therefore have an outstanding value for conservation. The region is recognized as a global centres of plant endemism by the WWF/IUCN. However this area does not benefit from any federal, national or international protection. There is general interest within academia for protection of some areas in the Sierra de Juárez, but there is no official plan to establish nature reserves (Valero et al. 2001). Proposals for additional priority areas required for conserving Oaxaca’s exceptional biodiversity are urgently needed (Illoldi-Rangel 2008). The Instituto de Biología of the Universidad Nacional Autónoma de México (UNAM) is conducting floristic inventories in the region but knowledge of the Sierra's flora remains so far limited (Valero et al. 2001). This species does not benefit from any legal protection. Alternatives to grazing should be sought at the type locality. Surveys should be conducted at the type locality and in potentially suitable neighbouring sites (i.e., high elevations openings in pine forest) to determine the current range and size of the population. The ecology, biology and dynamics of the population should be studied. Seeds should be collected for ex situ and germplasm conservation.