The Blackwood Division of the Duke Forest is near Durham, North Carolina (35° 58' 41.430"N, 79° 05' 39.087" W, 163 m asl).  Mean annual precipitation is 1140 mm, and mean annual temperature is 15.5 °C.  Soils are acidic Hapludalf, with a clayey loam in the upper 0.3 m, and clay below down to the bedrock at 0.7 m. Maximum soil moisture is 0.54 m3m-3.  The local topographic variations are small (<5% slopes).  The three vegetation types (abandoned Old Field - OF; Mid-rotation Pine Plantation - PP; & 80-100-year-old Oak-Hickory Type Deciduous Forest - DF; see figure and table) represent a typical land-use sequence in the piedmont region of N.C. The OF and PP cover types were established after a clear-cut and burn in 1983. Pine seedlings were planted (2 X 2.4 m), and natural regeneration added a large number of additional species. The Old Field is mowed every year to check the encroachment of pine and hardwood species.

	OF	PP	DF
Land-cover type	Old-Field	Pine Plantation	Hardwood Forest
Tree density (ha-1)	0	1730	311 (canopy) 810 (subcanopy)
Basal Area (m2 ha-1)		26.4	28.2
Leaf Area Index* (m2 m-2)	1.0 - 3.0	2.5-5.5	0.2-5.0
Canopy Height (m)	0.1 - 1	16	31
Tower Height (m)	5.5	24.0	40.0

*The range in Leaf Area Index delineates seasonal variation.

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