Texas Barberry (Mahonia swaseyi) is a rare, endemic evergreen shrub to the Texas Hill Country. That means it is limited to growing only in the area of Live Oak/Ashe Juniper savannah of the Edwards Plateau ecoregion. Westcave monitors the location, growth and overall health of each of over 20 individual plants currently found on the Preserve.

Texas Barberry is similar in appearance to the more common agarita (Mahonia trifoliolata), which can make identification confusing. Texas Barberry is composed of 5-9 leaflets as opposed to 3 leaflets found in the agarita. The two species can also hybridize where their ranges overlap, though there is very little published information on these hybrids. Much of what is known comes from field observation and identification notes based on leaf structure and bracteoles.