Effect of residual trees on natural and regeneration in a tupelo cypress swamp after 24 years

Abstract

Experimental harvests were made in a 500 acre non-alluvial swamp on the Francis Marion National forest in the mid 1960's to test for effects of residual trees on natural regeneration of the swamp tree species. Treatments were clear cut, leave 90, 30, and 15 trees per acre, and no cutting. All leave trees were swamp tupelo (Nyssa sylvatica var biflora), about 90 years old. First year seedling establishment of swamp tupelo varied from 12,460 seedlings per acre (s/a) with 30 leave trees per acre to 5,270 s/a with 15 leave trees per acre. However, within a few years after harvest, loblolly pine (Pinus taeda) seedlings became an important component of the regenerating stand and were the largest individuals on the site at age 24. Bald cypress (Taxodium distichum) was next in size. Swamp tupelo trees were smaller than the above species. All large loblolly pine occurred on hummocks whereas swamp tupelo occurred in the matrix of the swamp. Growth of swamp tupelo was sensitive to number of residual trees and appeared to stagnate at high densities. Pre- and post-harvesting measurements of water table levels showed that roads and harvesting had little or no affect on water table levels in the swamp. Hurricane Hugo reduced the basal area and density of loblolly pine in the treatment plots by as much as 80 % . It appears that periodic hurricanes may play an important role in reducing the stocking of loblolly pine in shallow swamps in coastal plain shallow swamps.

Citation

Hook, Donal D.; Buford, Marilyn A.; Harms, William R. 1992. Effect of residual trees on natural and regeneration in a tupelo cypress swamp after 24 years. In: Proceedings of the Biennial Southern Silvicultural Research Conference; 1992 November 17-19; Mobile, AL: 91-96.