The vegetation communities of Carlsbad Caverns National Park are diverse and, in most cases, beautiful. This diversity is further benefited by the position of the park at the intersection of the northern Chihuahuan Desert, southern Rocky Mountain, and southwestern Great Plains biogeographic provinces.
. Vegetation Map
Ecologists use the concept of "plant associations" to help describe and recognize patterns in the way vegetation occurs in the landscape. The park's vegetation map, completed in 2003, verifies the uniqueness and diversity of its vegetation. It documents 85 different plant associations in the park. These range from desert shrublands and semi-grasslands of the lowland basins and foothills up through montane grasslands, shrublands and woodlands of the highest elevations.
Of those 85 plant associations, 28 are new associations that were not previously described elsewhere.
The vegetation map documents that more than half the park is shrubland, with 17,858 acres (7,227 hectares) of montane shrubland and 9,295 acres (3,762 hectares) of desert shrubland. About a third of the park—14,586 acres (5,903 hectares)—is covered in various grassland associations. Other smaller map units include 1,753 acres (709 hectares) of arroyo riparian woodland and shrubland, 1,765 acres (714 hectares) of woodland, and 1,989 acres (805 hectares) of "other," which includes small areas of some very interesting communities, such as scattered herbaceous wetlands, the forested wetland at Rattlesnake Springs, and various cliff/rock/barren/arroyo communities.
The park's vascular plants includes about 900 species and subspecies.
The park's diverse ecosystem provides habitat for many plants that are at the geographic limits of their ranges. For example, the Ponderosa Pine reaches its extreme eastern limit here and Chinkapin Oak is at the western edge of its range.
There is more diversity of cacti in the Chihuahuan Desert than in any other region. Experts believe that this plant family originated here or to the south, and expanded out through the New World. The park's vascular plant list notes 26 species or subspecies of cacti, including two species that are federally listed.
The plant families with the most species in the park are species in the sunflower family, with 153 species, and grasses, with 135 species. There are more than 60 known species of the legume family and more than 30 each from the mustard and poinsettia families. Other groups with numerous representatives include the mint family (25), milkweed family (15), and ferns (13).