Nongame and Rare Species Program: Rare Plant Communities of Texas
Edwards Plateau: Bigtooth Maple Canyon Forest
Global Rank: G2
Description: This disjunct forest type is found on the lower slopes and floors of sheltered, mesic canyons in a small part of the southern Edwards Plateau from Kendall County west to Real County, Texas. The canopy is dominated by Acer grandidentatum (the “lost maples”) and Quercus muehlenbergii, often with Juniperus ashei, Q. buckleyi, Q. laceyi, Juglans major, Prunus serotina var. eximia, Fraxinus texensis, and occasionally Tilia americana var. caroliniana. The shrub stratum may include woody plants common in the surrounding landscape, such as Sophora secundiflora and Diospyros texana, as well as species characteristic of mesic canyons such as Ungnadia speciosa, Aesculus pavia var. flavescens, Lindera benzoin, Styrax platanifolius ssp. stellatus, Frangula caroliniana and Cornus drummondii. The ground layer may be sparse; common species include Carex edwardsiana, Passiflora affinis, Tragia nigricans, Spigelia texana ,and Verbesina virginica var. virginica. Chaetopappa effusa and T. nigricans are characteristic and distinguish this type from the similar community which occurs in the Lampasas Cutplain region in Bell County. Adjacent slopes are usually dominated by woodlands of Juniperus ashei and Quercus spp.
Species of Interest: Texas Snowbells (Styrax platanifoliusssp. texanus), Canyon Mock-orange (Philadelphus ernestii), Canyon Rattlesnake-root (Prenanthes carrii), Watson’s Milkpea (Galactia watsoniana), Canyon Bean (Phaseolus texensis), Darkstem Noseburn (Tragia nigricans).