The Piney Woods is a temperate coniferous forest terrestrial ecoregion in the Southern United States covering of East Texas, southern Arkansas, western Louisiana, and southeastern Oklahoma. These coniferous forests are dominated by several species of pine as well as hardwoods including hickory and oak. Historically the most dense part of this forest region was the Big Thicket though the lumber industry dramatically reduced the forest concentration in this area and throughout the Piney Woods during the 19th and 20th centuries. The World Wide Fund for Nature considers the Piney Woods to be one of the critically endangered ecoregions of the United States. The United States Environmental Protection Agency (EPA) defines most of this ecoregion as the South Central Plains. In Arkansas, the region is sometimes called the Arkansas Timberlands.

Setting The Piney Woods cover a area of eastern Texas, northwestern Louisiana, southwestern Arkansas and the southeastern corner of Oklahoma. They are bounded on the east by the Mississippi lowland forests, on the south by the Western Gulf coastal grasslands, on the west by the East Central Texas forests and the Texas blackland prairies, on the northwest by the Central forest-grasslands transition, and on the north by the Ozark Mountain forests. This area receives of precipitation annually.

Flora

The region has heavy to moderate rainfall, with some places receiving over of rain per year. Longleaf, shortleaf, and loblolly pines, along with bluejack and post oaks, dominate sandhills. A well-developed understory grows beneath the sparse canopy, and includes yaupon holly and flowering dogwood. Pine savannas consist of scattered longleaf and loblolly pines alongside black tupelos, sweetgums, and in acid soils along creeks sweetbay magnolias. Other common trees in this ecoregion include eastern redbud, river birch, red maple, southern sugar maple, and American elm. American wisteria, a vine, may cover groves of trees.

Two varieties of wetlands are common in the Piney Woods: bayous are generally found near rivers and sloughs are generally found near creeks. In bayous bald cypress, Spanish moss, and water lilies are common plants. Sloughs are shallow pools of standing water that most trees are not capable of growing in. Other species, such as the purple bladderwort, a small carnivorous plant, have found niches in sloughs. A baygall is another type of wetland found the Piney Woods and other forest of the Gulf Coast states in the USA.Watson, Geraldine Ellis (2006) Big Thicket Plant Ecology: An Introduction, Third Edition (Temple Big Thicket Series #5). University of North Texas Press. Denton, Texas. 152 pp. Texas Parks and Wildlife. Ecological Mapping systems of Texas: West Gulf Coastal Plain Seepage Swamp and Baygall. Retrieved 7 July 2020

Hardy species of prickly pear cactus and yucca can be found in the forests where deep sands occur.

The indigenous Texas trailing phlox (Phlox nivalis texensis), an endangered species, grows in the sandy soils of longleaf pine forests.

Fauna Mammals: Common species in the Piney Woods include white-tailed deer (Odocoileus virginianus), Virginia opossum (Didelphis virginiana), northern raccoon (Procyon lotor), striped skunk (Mephitis mephitis), eastern mole (Scalopus aquaticus), least shrew (Cryptotis parva), eastern gray squirrel (Sciurus carolinensis), eastern fox squirrel (Sciurus niger), and eastern cottontail (Sylvilagus floridanus). Somewhat less common are the northern river otter (Lontra canadensis), bobcat (Lynx rufus), gray fox (Urocyon cinereoargenteus), southern short-tailed shrew (Blarina carolinensis), North American beaver (Castor canadensis), and swamp rabbit (Sylvilagus aquaticus). Some carnivores such as the eastern spotted skunk (Spilogale putorius), ringtail (Bassariscus astutus), long-tailed weasel (Mustela frenata), American mink (Mustela vison), and red fox (Vulpes vulpes), are uncommon, rarely seen, and in decline. Over a dozen species of bats occur in the region, some migratory like the Brazilian free-tailed bat (Tadarida brasiliensis) and silvered-haired bat (Lasionycteris noctivagans), others are year-round residents like the Seminole bat (Lasiurus seminolus), evening bat (Nycticeius humeralis), Rafinesque's big-eared bat (Corynorhinus rafinesquii), a threatened species in Texas. Rodents found in the Piney Woods include the southern flying squirrel (Glaucomys volans), common muskrat (Ondatra zibethicus), Baird's pocket gopher (Geomys breviceps), woodland vole (Microtus pinetorum), and about 10 additional native rats and mice.Schmidly, D. J. 2004. The Mammals of Texas, 6th. Ed. University of Texas Press, Austin, Texas. xviii, 501 pp. Reid, Fiona A. 2006. Field Guide to Mammals of North America North of Mexico, 4th ed., Peterson Field Guide Series. Houghton Mifflin Company. New York. xx, 579 pp.

Several of the larger carnivores that once occurred in the Piney Woods are entirely extirpated, including the hog-nosed skunk (Conepatus leuconotus), red wolf (Canis rufus), jaguar (Panthera onca), and ocelot (Leopardus pardalis). The mountain lion (Puma concolor) and black bear (Ursus americanus) have also been extirpated from most areas; however, very rare sightings or remains are occasionally documented, likely representing wandering individuals rather than breeding populations.Louisiana Department of Wildlife and Fisheries, Conservation: Louisiana Department of Wildlife and Fisheries Verifies Cougar Sighting in Northeast LouisianaTexas Parks and Wildlife Department: Mountain Lions Stable populations of black bears occur in adjacent areas north and east of the Piney Woods and they appear to be slowly increasing in numbers and dispersing. As of 2020, however, the black bear is largely extirpated from most quarters, and rare in peripheral areas.Louisiana Department of Wildlife and Fisheries, Conservation: Louisiana black bear.Arkansas Game and Fish Commission: Help the AGFC keep tabs on Arkansas's bear population. With the clearing of forest and decline of the native predators (or competitors), the nine-banded armadillo (Dasypus novemcinctus), coyotes (Canis latrans), and black-tailed jackrabbit (Lepus californicus) have expanded their ranges eastward into the region. Other species have been introduced into the region such as the nutria or coypu (Myocastor coypus), house mouse (Mus musculus), roof rat (Rattus rattus), and Norway rat (Rattus norvegicus). Feral house cats (Felis catus) and feral pigs (Sus scrofa) pose threats to native fauna and are serious conservation concerns.

Birds: With some species migrating through in the spring and fall, others nesting in the spring and summer months, and still others wintering in the region, well over 300 species of birds occur in the Piney Woods. A few of the many year round residents include the wood duck (Aix sponsa), black vulture (Coragyps atratus), red-shouldered hawk (Buteo lineatus), American kestrel (Falco sparverius), wild turkey (Meleagris gallopavo), northern bobwhite (Colinus virginianus), American woodcock (Scolopax minor), greater roadrunner (Geococcyx californianus), red-cockaded woodpecker (Picoides borealis), loggerhead shrike (Lanius ludovicianus), northern mockingbird (Mimus polyglottos), brown thrasher (Toxostoma rufum), Carolina chickadee (Poecile carolinensis), brown-headed nuthatch (Sitta pusilla), pine warbler (Dendroica pinus), Bachman's sparrow (Aimophila aestivalis), and fish crow (Corvus ossifragus). Many additional species migrate from regions south and nest in the Piney Woods in the spring and summer, such as the anhinga (Anhinga anhinga), yellow-crowned night-heron (Nyctanassa violacea), little blue heron (Egretta caerulea), snowy egret (Egretta thula), purple gallinule (Porphyrula martinica), Chuck-will's-widow (Caprimulgus carolinensis), scissor-tailed flycatcher (Tyrannus forficatus), prairie warbler (Dendroica discolor), Swainson's warbler (Limnothlypis swainsonii), and painted bunting (Passerina ciris). Conversely, a different assemblage of birds migrate from the north to spend the winters months in the region, including the Canada goose (Branta canadensis), ring-necked duck (Aythya collaris), hooded merganser (Lophodytes cucullatus), blue-headed vireo (Vireo solitarius), Henslow's sparrow (Ammodramus henslowii), Le Conte's Sparrow (Ammodramus leconteii), and Smith's longspur (Calcarius pictus). A few species that once occurred in the region are now extinct like the passenger pigeon (Ectopistes migratorius), Carolina parakeet (Conuropsis carolinensis), ivory-billed woodpecker (Campephilus principalis), and Bachman's warbler (Vermivora bachmanii).Mulroy, Kevin (Editor-in-Chief). 2002. Field Guide to the Birds of North America, 4th edition. National Geographic, Washington, D. C. 480 pp. Terres, John K. 1996. The Audubon Society Encyclopedia of North American Birds. Wings Books, a division of Random House Value Publishing, Inc.. New York. N. Y. 1109 pp.