Pine plantation communities: how do we begin to manage for plant diversity?
Conservation of biological diversity is becoming a flagship issue on public and private forests worldwide while productivity increases are demanded. As concern for diversity. maintenance escalates, increasing pressure is being placed on the forestry community to understand the effects of intensifying silvicultural treatments on biodiversity and its sustainable management Intensity of management must increase to supply commodities demanded by the growing world population. Biodiversity conservation in.intensively managed forested regions will depend (at least partially) on species growing in tree plantations, their margins, streamside management zones, and right-of-ways. Within the Southeast, pine plantation acreage is projected to double by 2040, mainly replacing natural pine forests. Replacement and/or establishment of plantations occur through intensive harvesting, using herbicides and mechanical treatments, burning, planting closely-spaced genetically-improved seedlings, and often fertilizing. The singular or additive effects of all these treatments are often assumed to limit plant species richness and diversity, yet little has been documented to support or refute these assumptions. More indepth research is required by forest vegetation management scientists and other researchers from allied disciplines. To learn more about diversity changes following herbicide treatments for site preparation and release, I have led two teams in conducting both a region-wide research project at 13 locations in 7 states, and a study series in Central Georgia on 7 locations in 3 provinces. The following generalizations came from the findings of these studies as well as from other's related research.