The Piney Woods Forests stretch across eastern Texas, northwestern Louisiana, and southwestern Arkansas. This ecoregion includes parts of what is commonly known as the Big Thicket region of east Texas. The Piney Woods occupies the western extent of the Southeastern coastal plain and its vegetation reflects similarities with the communities found within the Southeastern Mixed Forests [NA0413] and the Southeastern Conifer Forests [NA0529]. Despite its name, Küchler (1985) classified this ecoregion as oak-hickory-pine forest. Little of the long-leaf pine forests that once dominated this ecoregion remain. Pine plantations are widespread and the effects of fire suppression have caused considerable ecological damage to this ecoregion.
Sandhill pine forests are one of the communities characteristic of the Piney Woods. Long-leaf pine (Pinus palustris) shares dominance with shortleaf pine (Pinus echinata) and loblolly pine (Pinus taeda). In this flatwood like habitat, pines dominate the overstory with a well-developed woody understory (Christensen 1988). Pine density is low, the herb layer is sparse, and exposed sandy tracts are common. Common associated trees are bluejack oak (Quercus incana) and post oak (Q. stellata), with a characteristic understory of Yaupon (Ilex vomitoria) and flowering dogwood (Cornus florida). Savanna-like areas occur on poorly drained soils and contain scattered individuals of longleaf and loblolly pine along with tupelo (Nyssa sylvatica) sweet gum (Liquidambar styraciflua) and magnolia (Magnolia virginiana). The interaction of moisture and fire frequency determine vegetation structure and composition (Ware et al. 1993). In other sections oaks and hickories are mixed in with pines.
Habitat Loss and Degradation
About three percent of the remaining habitat is considered intact. Bottomland forests around the Red River have been completely converted. Long-leaf pine areas have been converted to loblolly or slash pine plantations or severely fire suppressed. Urban development was a major cause of habitat loss in the early part of this century as was logging. Today, fire suppression is a major factor of habitat loss for fire-dependent species as is conversion to pine plantation.
Remaining Blocks of Intact Habitat
Remaining small fragments include:
•Fort Polk and Vernon District of the Kisatchie National Forest - central Louisiana
•Remainder (other districts) of Kisatchie National Forest - central and northern Louisiana
•Big Thicket National Reserve (very linear-shaped habitat block offering little core area) - eastern Texas
•Texas National Forests (Sabine, Angela, Davy Crockett, Sam Houston, all with lower level of protection and the last two heavily used for timber production)
•Sandylands (TNC reserve of about 2500 hectares) - east Texas
•Smaller fragments in adjacent areas of Arkansas and Louisiana
Degree of Fragmentation
Fire dynamics in this ecoregion are very much affected by fragmentation as are large carnivores (e.g. black bears). Expert assessment is that it will be difficult to restore corridors in this ecoregion and perhaps greater attention should be given to expanding existing areas.
Degree of Protection
Poor, and protected areas do not adequately represent typical vegetation. One of the major conservation initiatives in this ecoregion is the Pineywoods Conservation Initiative that seeks to maintain nearly 3,200 hectares of long-leaf pine forest.
Types and Severity of Threats
Conversion threats are continued conversion to pine plantations and to a lesser extent urban areas. The main degradation threat is considered to be fire suppression.
Suite of Priority Activities to Enhance Biodiversity Conservation
•Ensure better representation of major community types in protected areas (poor representation at present)
•Promote fire management and promulgate right to burn laws
•Work to conserve wilderness areas by removing fire suppression policies
•Continue inventory and identification of important sites for biodiversity and protect remaining areas
•Arkansas Natural Heritage Commission
•Louisiana Natural Heritage Program
•The Nature Conservancy of Arkansas
•The Nature Conservancy
•The Nature Conservancy of Louisiana
•The Nature Conservancy, Piney Woods
•The Nature Conservancy of Texas
•The Nature Conservancy - Southeast Regional Office
•Oklahoma Natural Heritage Inventory
•Texas Biological and Conservation Data System
Relationship to other classification schemes
The Piney Woods Forests includes parts of Omernik (1995) ecoregion #35 (South Central Plains), Bailey (1994) subregions 231E and 232F (Mid Coastal Plains and Coastal Plains and flatwoods, Western Gulf Section), and Küchler (1985) unit no. 101 (Oak-Hickory-Pine Forest).
Prepared by: A. Weakley, T. Cook, E. Dinerstein, K.Wolfe