Composition, structure, and dynamics of a pine-hardwood old-growth remnant in southern Arkansas

The Levi Wilcoxon Demonstration Forest (LWDF) was originally established by the Crossett Lumber Company in 1939 to promote forestry research and demonstration in the Upper West Gulf Coastal Plain of southern Arkansas. The reserve currently has at least 27 different overstory tree species, with loblolly pine (Pinus taeda L.), shortleaf pine (Pinus echinata Mill.), and white oak (Quercus alba L.) comprising the majority of stand basal area. Hardwoods are most numerous, dominated by shade-tolerant species such as red maple (Acer rubrum L.), flowering dogwood (Cornus florida L.), blackgum (Nyssa sylvatica L.), and winged elm (Ulmus alata Michx.), especially in the subcanopy and understory. Large pines, oaks, and sweetgum are scattered throughout the stand, with some individuals exceeding 100 cm DBH and 45 m tall. Overstory trees rarely proved sound enough to age, but some stumps, logs, and increment cores suggest that the dominant canopy pines are 100 to 150 years old, with the largest individuals exceeding 200 years. Pines contributed the greatest amount of coarse woody debris, The average volume of dead wood was noticeably less than other examples of old-growth upland forest in the eastem United States, attributable largely to salvage. Increased windthrow and the salvage of dead and dying pines have become the primary perturbations of the LWDR Without large-scale disturbance like catastrophic fire or logging, shade-intolerant pines, oaks, and sweetgum (Liquidambar styraciflua L.) will decline in prominence, to be replaced by more shade-tolerant species.