One of the most beautiful and pristine old-growth forests in the state, the 1,400-acre Lennox Woods Preserve is a vital refuge for several rare plant and animal species, all of which rely on the waters of Pecan Bayou, the largest undammed watershed in northeast Texas and what many consider the focus of the return of the black bear. The old-growth timber and cathedral-like canopy of these woods thought to be typical of the undisturbed floodplains throughout the state prior to the arrival of settlers.
Most of the woodlands in the area were sold for logging purposes, but these woods have been protected for four generations by the Lennox family, who originally acquired the property in 1863. The first parcel—170 acres—was donated in 1987 by Martha, David and Bagby Lennox. Another 206 acres were donated by Martha Lennox and the Lennox Foundation in 1990, after her brothers passed away; the preserve was dedicated in May of that same year.
Teams of zoologists and botanists have conducted intensive, seasonal inventories of the preserve's plant, bird, fish, mammal, reptile and amphibian populations to assess the area’s biological diversity and gauge the area’s ecological health. Presently, the preserve’s plant and animal communities appear to face few threats as long as the watershed remains undisturbed and neighboring woodlands are not logged further.
Lennox Woods contains one of the few remaining examples of fully mature, virgin timber found in the state, some greater than three feet in diameter. 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. The upland forest is a mixed evergreen-deciduous forest dominated by shortleaf pine, white oak, loblolly pine, southern red oak, red maple and various hickories. 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 hardwood forest 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 ground. In the occasionally flooded portions of the bottomland hardwood forest is one of the few extant populations of the globally threatened Arkansas meadow rue. The hooked buttercup and Wildenovi's sedge, two species that are rare in Texas, are also found here.
Lennox Woods Preserve is located along State Highway 37 in Red River County, about 10 miles north of Clarksville. More than 350 acres are open to the public, including the Martha Lennox Memorial Nature Trail, a 1.5-mile interpretive nature trail that features a variety of important trees and shrubs.