Treesearch

Thinning is a well understood concept used to manage density dependent factors at the stand level. This study evaluates the effect of planting density, cultural intensity, and thinning treatment on loblolly pine post-thinning individual tree development. The Lower Coastal Plain Culture/Density Study, has four initial densities, in combination with two cultural treatments, that were thinned at age 12 to the current density on the lowest initial density. Analysis of data six years post-thin for the Lower Coastal Plain focuses on the effects of cultural intensity and density regime effects...

Pine stand density is a key determinant of damage resulting from attacks by the southern pine beetle (SPB, Dendroctonus frontalis Zimm.). High-density stands of maturing loblolly pine (Pinus taeda L.) are at high risk for losses to SPB, and reducing stand density is the primary tool available to forest managers for preventing and mitigating damage. Field studies are expensive and inflexible for evaluating various stand treatments over large areas and long time periods, especially with unpredictable SPB population levels. To address these shortcomings, and to provide guidance on silvicultura...

Recent advances in somatic embryogenesis permit large numbers of clonal loblolly pine (Pinus taeda L.) to be produced and deployed. Clones may have greater growth (mean annual increment exceeding 30 cubic meters per hectare per year), greater stand uniformity and may be more susceptible to genotype by environment interactions when they are deployed in intensively managed plantations. Consequently, large numbers of clones will need testing under a range of silvicultural treatments to effectively and efficiently identify those that are best for deployment. Crown ideotypes are described by...

The purpose of this research is to analyze thinning response in basal area and height growth of residual loblolly pine trees growing in plantations located in the West Gulf Coastal Plain. Thinning is a well-known silvicultural practice that increases the growing space available to desirable trees by removing competing trees.

The Pax winter storm of February 2014 caused widespread damage to forest stands throughout the southeastern U.S. In a long-term study of savanna plant community restoration at the Savannah River Site, Aiken, SC, precommercial thinning (PCT) of 8- to 11-year-old plantations of longleaf pine (Pinus palustris) in 1994 reduced their susceptibility to stem bending and breakage from the storm 20 years later, despite the occurrence of an intensive commercial thinning just two years before the storm. Tree mortality in areas that had received PCT (25 percent) was less than where PCT had not...

Longleaf pine (Pinus palustris) seedlings were cultured with air lateral root pruning (side-vented containers, VT) or without (solid-walled containers, SW). Seedling root system morphology and growth were assessed before planting and 8 and 14 months after planting. Although VT seedlings had greater root collar diameter than the SW before planting, seedling height and ground line diameter were not affected by root pruning 14 months after planting. Root pruning did not affect seedling biomass. However, root pruning changed the patterns of biomass allocation. Before planting, VT seedlings...

By the fifth anniversary of the America’s Longleaf Restoration Initiative in 2014, the decline in longleaf pine (Pinus palustris L.) appears to have been reversed. The area in longleaf pine-dominated stands currently exceeds 4 million acres, up from a low of about 3 million acres two decades ago. A major contribution to this reversal has been the recent establishment of more than 500,000 acres of longleaf pine plantations. However, the plantation approach has limitations in an environment where stand establishment costs exceed $300 per acre, when large-diameter sawlogs currently bring...

Many longleaf pine stands across the range have suffered decades of fire exclusion, leading to declines in plant and animal biodiversity and complicating restoration and management efforts. Recent research on this topic has focused on the physiological response of overstory longleaf pines and the fuel characteristics of the surrounding forest floor. In small-scale and operational prescribed fires, post-fire pine mortality is tightly linked to basal duff (lowermost fermentation and humus forest floor horizons) consumption and, where present, crown scorch. Pines with substantial duff...

Common walnut (Juglans regia L.) is cultivated in temperate regions worldwide for its wood and nuts. The complete chloroplast genome of J. regia was sequenced using the Illumina MiSeq platform. This is the first complete chloroplast sequence for the Juglandaceae, a family that includes numerous species of economic importance. The chloroplast genome of J. regia was 160 367 bp in length, with 36.11% GC content. It contains a pair of inverted repeats (26 035 bp) which were separated by a large single copy (89 872 bp) and a small single copy region (18 425 bp). A total of 137 genes were...