Document: STE-3-40-24

Effects of site preparation and vegetation control on the plant community and successional dynamics of a managed pine plantation.

JEFFRIES, S.B.*, T.R.WENTWORTH and H.L.ALLEN

North Carolina State University, Raleigh, NC 27695-8002 USA ¹

Abstract:
Over the last several decades, researchers have expressed concern over the long-term sustainability of managed forests in the southeastern United States. In particular, the loss of diversity in so-called 'monoculture' plantations, and the alteration of successional dynamics, have received considerable attention. We conducted a comparative study of silvicultural practices in a third rotation loblolly pine plantation in the Piedmont of North Carolina. Following harvest, a 2 by 2 factorial experiment was established using two site preparation (chop versus shear, pile, and disk) and two cultural (herbicide versus no herbicide) treatments. Presence/absence of vascular plant taxa was determined for each of the four treatments across three blocks in years 1, 2, 6, and 18 and analyzed using non-metric multidimensional scaling. Analysis of the data from years 1, 2, and 6 showed compositional trends related to succession and site preparation, with herbicide and block effects playing a lesser role. However, preliminary analyses incorporating data from the eighteenth year of the study indicate convergence of composition across treatments, although lingering block effects can still be seen. We can infer from these results that high intensity silvicultural practices, such as site preparation and use of herbicides, do not result in the disruption of successional dynamics. Although the stands appear quite different as a result of the treatments imposed, they are all maintaining populations of the same late successional taxa.

Keywords: managed forests, ordination, vegetation analysis, non-metric multidimensional scaling, succession

This abstract is being presented at: 3:30 PM in session:
Poster Session #17: Vegetative Analysis.