Riparian zone seedling establishment, growth, dynamics, and the influence of Rhododendron maximum soil moisture: forest floor data at the Coweeta Hydrologic Laboratory from 1997 to 2000

The effect of Rhododendron maximum, a dominate species in the riparian zones of the Southern Appalachians, on carbon, water, and nutrients en route to the streams is an ongoing study in the LTER research program at Coweeta Hydrologic Laboratory. To study seedling establishment, growth, and dynamics in riparian zones one m2 quadrats have been established. There are four sites which include one treatment site, where the rhododendron has been removed from the riparian zone, one hurricane site, where there is extensive disturbance from Hurricane Opal, and two control sites, one upslope from the treatment site and one upstream from the hurricane site. Each of these fours sites have ten randomly located natural regeneration one m2 quadrats as well as four randomly located replicates of three adjacent one m2 quadrats. In each of the three adjacent quadrats, the litter was removed from the lower half to determine the effect of litter on the germination and growth of seedlings. Two of the adjacent quadrats have been broadcast seeded with Acer rubrum, Liriodendron tulipifera, and Quercus rubra. In one of the two quadrats that have been broadcast seeded, a predator exclusion mesh screen, 1m x 1/2m with " openings, has been installed in the quadrat to determine the effect of small mammal predation on regeneration. Quadrats were installed on 24 April 1997 and an initial vegetation survey was conducted in May 1997. All seedlings were permanently tagged at this time and quadrat physical characteristics such as slope, aspect, and distance from stream were recorded. Broadcast seeding was done on 21 May 1997. Each year censuses will be conducted in spring and fall on each quadrat and seedling species, density, age, and annual height growth will be recorded. This project will help to document the effect of Rhododendron maximum on regeneration in the riparian areas as well as the effect of hurricane disturbance on regeneration.