Crown structure, absorbed photosynthetically active radiation (APAR) and growth were analyzed in 300 replicated loblolly (Pinus taeda L.) and slash pine (Pinus elliottii Engelm. var. elliotti) clones to: (1) quantify genetic variation in crown structural traits, growth and APAR at the species, family and clonal levels; and (2) estimate within-family genetic and environmental influences on measu...

Determining how anthropogenic disturbances affect site productivity through bioassays requires a complete understanding of both overstory and understory vegetation. This study was installed in 1997 to determine how soil compaction and intensive harvesting affected the inherent site productivity of pine stands on the western boundary of loblolly pine’s (Pinus taeda L.) natural range. We measured...

Replacement of the average numerator relationship matrix derived from the pedigree with the realized genomic relationship matrix based on DNA markers might be an attractive strategy in forest tree breeding for predictions of genetic merit. We used genotypes from 3461 single-nucleotide polymorphism loci to estimate genomic relationships for a population of 165 loblolly pine (Pinus taeda L.) indi...

Mention of trade names is solely to identify materials used and does not imply endorsement by the U.S. Department of Agriculture. Discussion of herbicides in this paper does not constitute recommendation of their use or imply that uses discussed here are registered. Herbicides that are handled, applied, or disposed of improperly are a potential hazard to the applicator, off-site plants, and env...

Accurate and affordable measurements of upper-stem diameters are now possible thanks to recent advances in laser technology. Measurement of the midpoint upper-stem diameter can be employed to improve the accuracy of diameter predictions along the tree bole. Felled-tree data from a loblolly pine (Pinus taeda L.) plantation was used to evaluate two approaches: (1) calibrating a segmented taper eq...

Seedlings from four families of loblolly pine (Pinus taeda L.) were grown in capped open-top chambers and exposed to three different weekly moisture regimes for 13 weeks. Moisture regimes varied in intensity and frequency of simulated rainfall (irrigation) events; however, the total amounts were comparable. These simulated treatments were chosen to simulate expected changes in rainfall variabil...

The degree to which forest ecosystems provide a long-term sink for increasing atmospheric CO(2) depends upon the capacity of trees to increase the availability of growth-limiting resources. It has been widely speculated that trees exposed to CO(2) enrichment may increase the release of root exudates to soil as a mechanism to stimulate microbes to enhance nutrient availability. As a first test t...

Soil loss and nutrient concentrations in runoff were evaluated to determine the effects of site preparation burning on a recently harvested loblolly pine (Pinus taeda L.) site in east Texas. Soil and nutrient losses prior to treatment were approximately the same from control plots and pretreatment burn plots. Nutrient analysis of runoff samples indicated that the prescribed burn caused increase...

The objectives of this study were to examine the effects of stand development and soil nutrient supply on processes affecting the productivity of loblolly pine (Pinus taeda L.) over a period approximately equal to a pulpwood rotation (18 years). The experiment consisted of a 2 x 2 factorial combination of complete and sustained weed control and annual fertilization treatments (C: control treatm...

(ed. B.P. Singh) 427 pine (Pinus elliottii var. elliottii). Of note, the former two are also considered to be species of concern for conservation (Erickson et al., 2012) due to long-standing land management practices that have favoured loblolly pine. Similarly to loblolly pine, although on a smaller scale, slash pine has been widely planted and managed for wood and fibre production. Because of ...