A Comparison of Planted Loblolly Pine (Pinus taeda) Growth in Areas Receiving Different Levels of Establishment Regime Intensity

Abstract

Management intensity of southeastern US pine (Pinus spp.) plantations has increased during past decades, emphasizing timber production. Managers need more information about tree growth responses to different establishment intensities to successfully meet their economic and ecological objectives. We established a comparison of five loblolly pine (P. taeda) plantation establishment regimes in the Mississippi Lower Coastal Plain (LCP, n = 4), using a gradient of mechanical and chemical site preparation and herbaceous weed control intensities. Treatments varied from “low intensity” to “high intensity” and were expected to produce a gradient in vegetative and pine growth response. We monitored herbaceous and woody ground cover, woody stem density, pine survival, and pine growth during years one and two post-treatment (2002 and 2003). Herbaceous cover, woody cover, and woody stem density decreased as treatment intensity increased. Pine survival was less on Treatment 5 and decreased slightly on all treatments during 2003. Pine height and diameter increased as treatment intensity increased, except for the treatment with no mechanical preparation, indicating the importance of subsoiling and bedding in the LCP. After two growing seasons, a combination of mechanical and chemical site preparation followed by one or two years of broadcast herbaceous weed control maximized pine growth.