PARENT SESSION
Oral Session # 6: Fire Ecology I: Structure and Demographics
Presiding: R Parmenter
Monday, August 4. 8:00 AM to 11:30 AM, SITCC Meeting Room 105.

Fire suppression and Quercus falcata seedling recruitment in southeastern forests.

Schnurr, Jaclyn^*,1, Collins, Beverly², ¹ Sheldon Jackson College, Sitka, AK² Savannah River Ecology Lab, Aiken, SC

ABSTRACT- Without fire, southeastern pine forests undergo succession to mixed pine-hardwood stands. We transplanted Quercus falcata (southern red oak) seedlings into 10 sites on the Savannah River Site (SRS), near Aiken, SC, to determine if this common upland oak shows increased recruitment in the absence of fire. The sites included unmanaged dry ridgetop sandhills (N=2) and more mesic pine-hardwoods on slopes (N=2), and managed stands with different burn histories [unburned since 1950 (N=2), burned in the mid-1990s (N=2) and recently burned (N=2)]. We asked: Does survival of transplanted Q. falcata seedlings differ among community types and land management treatments? We measured initial seedling height and stem diameter, and soil moisture in each plot in April, 2002. We censused survival in May, July, and October and measured seedling growth in October. Canopy openness above each plot was measured in midsummer. Seedling survival differed among the sites, with greatest survival at the sites unburned since 1950. Canopy openness significantly decreased seedling survival, while soil moisture in May increased survival. However, there was no effect of community type on seedling growth: seedlings that survived grew equally well in all sites. Our data indicate that fire suppression favors establishment of Q. falcata , ultimately decreasing pine dominance in upland southeastern forests.

Key words: southern red oak, abiotic controls, seedling recruitment, fire