Treesearch

Short-rotation cottonwood plantations were established on a marginal agricultural site in the lower Mississippi Alluvial Valley in southeast Arkansas using two known clones (S7C20 and ST-66) and nurseryrun cottonwood stock (MIXED) from the Louisiana Department of Agriculture and Forestry nursery. The cottonwood was grown for five seasons and harvested in the winter of 2013-2014. Harvesting was done by a chainsaw (control) and a mechanical tree shear (treatment). Regeneration in the form of stump sprouts was evaluated after one growing season for survival, total number of sprouts, sprouts...

We used National Oceanic and Atmospheric Administration weather data and historical records of cone crops from across the South to relate weather conditions to the yield of cones in 10 longleaf pine (Pinus palustris Mill.) stands. Seed development in this species occurs over a three-year time period and weather conditions during any part of this span could have varying effects on the final seed crop. Weather had a significant effect on cone crops, but the relationship across many years was complex and could not be attributed to any small subset of variables.

Within the temperate, deciduous forests of the eastern US, diverse soil-fauna communities are structured by a combination of environmental gradients and interactions with other biota. The introduction of non-native soil taxa has altered communities and soil processes, and adds another degree of variability to these systems. We sampled soil macroinvertebrate abundance from forested sites in Missouri (MO), Michigan (MI), Massachusetts (MA), and New Hampshire (NH), with the objective of comparing community assemblages and evaluating the role of invasive earthworms along the temperature–product...

Summary We used long-term population data for rosyside dace (Clinostomus funduloides), a numerically dominant member of a stochastically organised fish assemblage, to evaluate the relative importance of density-dependent and density-independent processes to population persistence. We also evaluated the potential impacts of global climate change (GCC) on this species and predicted how directional environmental changes will affect dace. We sampled two 30 m permanent sites in spring and autumn in the Coweeta catchment for rosyside dace density using three-pass electrofishing between 1984 and...

Climatic effects on tree recruitment will be determined by the interactive effects of fecundity and seed predation. Evaluating how insect and vertebrate seed predators mediate tree reproductive responses to climate depends on long-term studies of seed production, development, and predation. In this study, our objectives were to (1) assess the effects of interannual climate variation on seed abortion rates, (2) assess the impact of seed density on predation rates, and (3) examine the degree to which density-dependent seed predation would amplify or dampen interannual variation in fecundity...

The effect of a silvicultural operation, row thinning at two intensities (single row, SR, and double row, DR, thinning), on soil properties and biomass were investigated in selected 28 year-old slash pine (Pinus elliotti) plantations in the Apalachicola National Forest. Stands were thinned in May 2011 and burn regimes were executed during dormant seasons. Indicators of changes in soil physical properties and biomass were evaluated in this work. Response variables included soil bulk density, stand basal area, and biomass. Stand basal area was consistently highest across locations in the...

Eucalyptus short rotation woody crops (SRWC) with superior genotypes are promising in central and south Florida due to their fast growth, freeze resilience, coppicing ability, and site tolerance. Four Eucalyptus grandis cultivars, E.nergy™ G1, G2, G3, and/or G5, were established in 2009 at varying planting densities on a reclaimed clay settling area (CSA) in phosphate mined land in central Florida and a bedded former citrus site in southern Florida. Planting densities were 1025, 2050, and 3416 trees/acre on the CSA, and 581, 869, 1162, 1452, and 1742 trees/acre on the citrus site. Modified...

New or retrofitted wood-fired energy plants have increased demand for woody biomass in the stateof Virginia. Loblolly pine (Pinus taeda) commonly serves as a feedstock for these energy plants. Pulpwood conventionally requires a minimum diameter of 4 inches diameter at breast height (DBH) for merchantability, whereas a minimum merchantable diameter for biomass is currently undefined. A harvesting case study was completed during the first thinning of a 15 year-old loblolly pine stand in the Virginia Coastal Plain to determine production rates and costs while harvesting densely stocked small...

Susceptibility of Lymantria monacha larvae to Entomophaga maimaiga was investigated under laboratory and field conditions, using larvae of the natural host, Lymantria dispar, as positive controls. In laboratory bioassays, L. monacha and L. dispar were injected with protoplasts of two isolates of E. maimaiga and mortality was monitored for 20 days. While virtually all injected L. dispar died, with ST50s (median survival times for 50% of insects injected with the two isolates) of six - seven days, only 65.6-86.7% of the injected L. monacha died, with ST50s of 11-17 days. Both isolates...

Eastern cottonwood (Populus deltoides) has received a substantial amount of interest from invitro studies within the past decade. The ability to efficiently multiply the stock of established clones such as clone 110412 is a valuable asset for forest endeavors. However, a common problem encountered is initiating adventitious rooting in new micropropagation protocols. Stem segments were collected from bud-broken 1 year old clone 110412 cuttings, sterilized, and stimulated to initiate shoots. Developed shoots (~2 cm in height) were excised and placed into one of three rooting media that...