Tallahatchie Experimental Forest
The 1,416-ha Tallahatchie Experimental Forest, located in the Holly Springs National Forest near Oxford, Mississippi, was created in 1950. It is administered by the Southern Research Station’s Center for Bottomland Hardwood Research at Oxford. Much of the Tallahatchie lies within the floodplain of the Little Tallahatchie River. It encompasses several small basins whose streams flow into the Little Tallahatchie River upstream of Sardis Reservoir. Upland portions of the forest include the headwaters of two additional watersheds, one draining into the Little Tallahatchie and the other into the Sardis. The Tallahatchie was established to study the relationships among hardwood forests, flooding, and soil erosion. The forest and associated hydrological research provided support for a large and perhaps unprecedented federal reforestation and soil stabilization effort, the Yazoo-Little Tallahatchie Project, which was conducted on the upper coastal plain of northern Mississippi from 1949 to 1985. Recent research on the Tallahatchie has focused on the response of plants and birds to altered fire regimes.
Three small watersheds (the Pine-Hardwoods Watersheds) were established in 1959 about 0.6 km east of the Tallahatchie. These watersheds have been informally considered part of the forest since establishment. Ten small watersheds and 10 nested, subwatersheds were installed in 1980-82.
Located in the upper coastal plain, the Tallahatchie has hot, humid summers and fairly mild winters with occasional ice and snowstorms. Annual precipitation in Oxford averages 1,321 mm and is distributed evenly throughout the year. The growing season lasts about 218 days. Average temperatures are 6.1 °C in January and 26.6 °C in July. Brief convective summer storms of high intensity are common. Most winter precipitation is cyclonic, and soils occasionally freeze to shallow depths.
Soils on the Tallahatchie consist of predominantly coastal plain sandy loams and smaller amounts of silt loams of loessial origin. Coastal plain soils are principally Ruston, and loessial soils are Lexington, Loring, and Grenada. Infiltration rates greatly exceed all but the most extreme precipitation intensities.
Forest cover on the Tallahatchie is 55- to 65-year old mixed stands of shortleaf pine and hardwoods, (largely white and red oak and hickories), which have been only minimally disturbed since establishment. Recent plant surveys revealed as many as 90 species of saplings and herbaceous plants. This amount is likely to increase when all hickory and other overstory species are included.
Long-term data bases include the amount and intensity of rainfall (1954 to 2001), humidity and air temperature (1954 to 1989), stormwater runoff from Pine-Hardwoods watersheds (1959 to 1997; one is ongoing). There are other data sets on hydrology, erosion, soils, and plant measurements.
Research, Past and Present
Research at the Tallahatchie has included the following topics:
- Sediment yields and runoff rates from small, undisturbed forested basins and from small, logged basins
- Influence of small mammals on stormflow responses of pine-covered catchments
- Hydrologic effects of harvesting methods for mature shortleaf pine-hardwoods
- Responses of plant and bird communities to fire regimes
- Correlations between tree species composition and changes in fire frequency
- Historically important fire/disturbance regimes in oak-pine forests of north Mississippi
- Relationships between avian community structure and prescribed burning
- Relationships between nest success in bird species of concern and prescribed burning
- Effects of simulated fire on flowering of a fire-adapted forb in infrequently burned oak-pine forests
- Connectivity and population dynamics of fishes among various flood-plain habitat types over seasons and years of different flood-plain inundation levels
- Effects of cool-season prescribed fire on herbaceous, understory, and overstory vegetation
Major Research Accomplishments and Effects on Management
At the Tallahatchie, effects of harvesting on runoff and erosion rates from small basins were quantified and our understanding of changes from historic fire regimes and of the effects of prescribed burning on plants and birds were greatly increased.
Scientists from the University of Mississippi and Mississippi State University have worked on the Tallahatchie.
The Tallahatchie provides opportunities for ongoing hydraulic studies of small basins with long-term data going back more than 40 years. Thus, researchers can examine hydrologic changes in the context of forest aging and climate change. The Tallahatchie’s lowland areas provide a rare opportunity to examine aquatic processes in relatively undisturbed, second-growth, flood-plain forests. The Tallahatchie also is an ideal site for studying the role of prescribed fire in restoration and biodiversity conservation.
An unused fire lookout tower and one warehouse are located on the Tallahatchie. There are about 11.3 km of improved USDA Forest Service roads (dirt) and 8.7 km of gated or unimproved roads. One gated road leads to an unimproved dirt boat-launch ramp on the Little Tallahatchie River.
Lat/lon: 34°30'10"N, 89°26'17"W (View this location on a map)
USDA Forest Service
Southern Research Station
Oxford, MS 38655