SREL Reprint #1997

Seasonal growth patterns of Nyssa sylvatica var. biflora, Nyssa aquatica, and Taxodium distichum as affected by hydrologic regime

B.D. Keeland and R.R. Sharitz

Savannah River Ecology Laboratory, Drawer E, Aiken, SC 29802, USA

Abstract: Hydrologic regime is a major influence on the growth of wetland plants. We examined seasonal growth patterns of three wetland tree species, Nyssa sylvatica var. biflora (Walter) Sargent, Nyssa aquatica L., and Taxodium distichum (L.) Rich., to determine responses to variations in hydrologic regime. Five study sites were chosen in two river-floodplain swamps to represent a gradient of hydrologic regimes, and the weekly changes in diameter of over 600 mature trees at these sites were measured with dendrometer bands throughout two growing seasons. Total growth, time of growth cessation, and length of the growth phase of canopy trees of all three species differed significantly among hydrologic regimes. Nyssa sylvatica var. biflora and N. aquatica achieved greatest growth under deep periodic flooding. Maximum growth of T. distichum occurred with shallow permanent flooding. Subcanopy trees differed less among hydrologic regimes than canopy trees. These results suggest that modifications of natural hydrologic regimes can cause short-term changes in tree growth and have long-term effects on the dynamics of forested wetlands.

SREL Reprint #1997

Keeland, B.D. and R.R. Sharitz. 1995. Seasonal growth patterns of Nyssa sylvatica var. biflora, Nyssa aquatica, and Taxodium distichum as affected by hydrologic regime. Canadian Journal of Forest Research 25:1084-1096.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).