Fall 2005

What Can Experimental Forests Teach Us Fragmentation?

Since the 1920s, the USDA Forest Service has maintained a system of experimental forests to test hypotheses and collect longterm data about the ecological effects of fire, grazing, insect infestations, air pollution, and other disturbances. In the South, researchers from Federal agencies and universities use 15 active experimental forests for studies ranging from the practices needed to maintain healthy forests, to the water fi ltration functions of forests, to habitat restoration for endangered species.

Experimental forests are some of the few places in the United States where longterm data are collected about forests and how they change over time. These living laboratories also serve as demonstration sites where cooperators and landowners can see the results of different forest management options.

In the early 1900s, Southern Appalachian forests were extensively grazed by livestock. Steep mountain land was cleared and planted with corn. Logging was done with little regard for erosion from roads and skid trails. Such land was not wanted by private individuals and could be bought for delinquent taxes.

In 1933, the USDA Forest Service established the Coweeta Hydrologic Laboratory for a program of watershed management research. Early studies on erosion control and soil stabilization for roadbanks and abandoned agricultural land led to the realization that further work required complete watershed instrumentation to provide continuous measurements of stream flow and precipitation. An intensive program of weir construction began at Coweeta in 1934 along with a network of 56 rain gages, numerous groundwater wells, and meteorological stations. (...continued...)