In fact, the Texas Forest Service aged one post oak on the preserve at over 300 years old and a loblolly pine at nearly 150 years old. Common components of the understory and shrub layers are dogwood , American beautyberry , mulberry and farkleberry . The ground layer has clumps of perennial grasses and sedges. The bottomland vegetation is dominated by water oaks , willow oaks , bur oaks , overcup oaks , sweetgum and some hickory species. The understory has small trees such as musclewood , winged elm and bluebeech .
Various sedges are abundant throughout the groundlayer.
Limited to the occasionally flooded portions of the bottomland hardwood forest is the ecologically unique presence of the only extant population of the globally threatened Arkansas meadow rue . The hooked buttercup and Wildenovi's sedge , two species that are rare in Texas, are also found in the bottomland forest. The primary focus of the preserve's management program involves on-going cataloging of resident species. Teams of zoologists and botanists already have conducted intensive, seasonal inventories of the preserve's plant, bird, fish, mammal, reptile and amphibian populations. These studies provide a clear picture of the biological diversity of the area.