PARENT SESSION
Poster Session 2: Forest Ecology
Monday, August 8, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal
Long-term successional trends in an oak-dominated forest in central Missouri.
Coonley, Angela *,1, Pallardy, Stephen1, 1 Department of Forestry, Columbia, MO, USA
ABSTRACT- Changes in species composition and forest structure were studied over a 36-year period at the Baskett Research and Education Area (BREA) in central Missouri. Permanent plots were established in 1968, the tree (>8.75cm) and sapling (<8.75 cm) dbh was measured, and species recorded. Plots were classified as dry ridge and slope, mesic slope, glade-like, or bottomland. The plots were resampled in 2004. Generally, dominant white oak (Quercus alba) tree basal area increased but density declined or remained constant. Maple (mostly Acer saccharum, with a small contribution of A. nigrum) tree density, basal area and importance values increased in the dry ridge and slope and mesic slope sites. Eastern redcedar (Juniperus virginiana) tree density, basal area and importance values increased on glade-like sites. Regeneration of oaks (Quercus spp.) has declined drastically, as shown by much reduced sapling density in all size classes and plot types. Larger sapling size classes of maple showed an increase in density; however, by 2004 Acer density in the smallest sapling size class had declined by almost 90% compared to 1968 in all plot types. This trend might have resulted from an increase in herbivory from high population levels of white-tailed deer (Odocoileus virginianus) in the region, which have been monitored in nearby Rock Bridge Memorial State Park. Because of the potential effect of herbivory, the long-term Acer successional trends in BREA remain unclear. DCA ordination models currently show that glade-like sites are moving toward J. virginiana dominance in glade-like sites and increased Acer importance in dry ridge and slope and mesic slope sites. At present, Acer is showing an increased presence in the overstory. Quercus still dominates the overstory, but with little to no oak in the regeneration a decline in oak importance in the future is virtually assured.
Key words: forest succession, oak-hickory forest, Quercus, Acer