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The long-term effects of soil acidification on the development of a young aggrading Appalachian forest were examined after 21 years of continuous treatment. Beginning with a clearcut harvest in 1997, annual ammonium sulfate (N+S) and ammonium sulfate with lime (N+S+LIME) treatments were aerially applied to a developing forest. The lime treatment was designed to counteract the acidification of the nitrogen and sulfur amendments. After 21 years, the N+S and N+S+LIME treatments had little impact on total woody biomass accumulation relative to the control. There were significant differences among species and treatment responses with respect to woody biomass accumulation, however. Biomass of Prunus pensylvanica was about twice as much as any other species in N+S and N+S+LIME treatments but was similar to Liriodendron tulipifera and Betula lenta on control areas. Treatment effects were not significant for average tree diameter or stem density, although both varied among the six tree species with the highest importance values. The importance value of P. pensylvanica decreased by almost half in the last 6 years due to mortality, but this was not associated with either the N+S or N+S+LIME treatments. The dynamic nature of this short-lived tree species is potentially masking any effects of the N+S or N+S+LIME treatments to date. Study Implications: We examined the long-term impact of nitrogen and sulfur additions with and without lime on forest stand development. After 21 years, the forest showed little change in aboveground woody biomass, although the distribution of biomass among species was affected by the treatments. Prunus pensylvanica (pin cherry) accumulated the greatest biomass on N+S and N+S+LIME treatments relative to the untreated areas. However, P. pensylvanica is a short-lived species, and our data show it is declining. It is unclear whether the treatments are having minimal impacts or they are being masked by the early dominance and subsequent mortality of P. pensylvanica.

Shrub willow (Salix spp.) has been a focus of international efforts to develop renewable alternatives for fossil fuels and to sequester carbon from earth’s atmosphere. In the central Appalachian region of the eastern U.S., short rotation willow could be grown on the significant amount of reclaimed mine land, which would promote economic opportunities for these lands. The objective of this study was to examine various establishment treatments designed to overcome common properties of mine soils: high rock fragment content that causes planting difficulties and reduced water- and nutrient-availability. Three shrub willow clones (Fish Creek, Preble, and SX61) were planted using six planting/fertilizer treatments. The planting treatments compared a horizontal planting method to traditional vertical planting of cuttings. Fertilizer treatments compared no fertilization to controlled release and traditional fertilizer at a rate of 140 kg N ha−1. After two growing seasons, Preble outperformed the others in both survival and production but the influence of fertilizer treatments was inconsistent and varied by clone. Survival and growth for horizontally-planted cuttings was 46% relative to vertically planted cuttings at 83%. Results of this study will be used to direct future establishment practices for willow on reclaimed mine soils in West Virginia.

Biodiversity patterns across geographical gradients could result from regional species pool and local community assembly mechanisms. However, little has been done to separate the effects of local ecological mechanisms from variation in the regional species pools on bacterial diversity patterns. In this study, we compare assembly mechanisms of soil bacterial communities in 660 plots from 11 regions along a latitudinal gradient in eastern China with highly divergent species pools. Our results show that β diversity does not co-vary with γ diversity, and local community assembly mechanisms appear to explain variation in β diversity patterns after correcting for variation in regional species pools. The variation in environmental conditions along the latitudinal gradient accounts for the variation in β diversity through mediating the strength of heterogeneous selection. In conclusion, our study clearly illustrates the importance of local community assembly processes in shaping geographical patterns of soil bacterial β diversity., The relative importance of regional species pool and local assembly processes as drivers of beta diversity is unclear. Here the authors investigate soil bacterial diversity patterns along a 3700-km latitudinal gradient in Chinese forests, finding that community assembly processes differ based on environmental heterogeneity.

Tree death is a natural part of forest dynamics, yet is not often studied over long periods, particularly in temperate mixed-species hardwood stands. In this study, we evaluated stand dynamics of four reference plots on each of the West Virginia Long-term Soil Productivity (LTSP) Studies. The Fork Mountain LTSP Study was initiated in 1996 and the Middle Mountain LTSP Study in 1997. The two locations represent distinct stand types (mixed mesophytic and cherry-maple) and site conditions (elevation, parent material, aspect). We found that after 20 years, there were differences in patterns of mortality and ingrowth between the two sites. Mortality rates ranged from 1.5 to almost 5 percent for a 5-year period on Fork Mountain to 1 to 1.5 percent on Middle Mountain. Generally, ingrowth exceeded mortality on Fork Mountain, while the reverse was observed on Middle Mountain. Possible reasons for differences in mortality and ingrowth between the two sites include differences in species composition related to soil and site characteristics and differences in past disturbance that have created different stages of stand development.

Elevated acid deposition has been a concern in the central Appalachian region for decades. A long-term acidification experiment on the Fernow Experimental Forest in central West Virginia was initiated in 1996 and continues to this day. Ammonium sulfate was used to simulate elevated acid deposition. A concurrent lime treatment with an ammonium sulfate treatment was also implemented to assess the ameliorative effects of base cations to offset acidification. We show that the forest vegetation simulator growth model can be locally calibrated and used to project stand growth and development over 40 years to assess the impacts of acid deposition and liming. Modeled projections showed that pin cherry (initially) and sweet birch responded positively to nitrogen and sulfur additions, while black cherry, red maple, and cucumbertree responded positively to nitrogen, sulfur, and lime. Yellow-poplar negatively responded to both treatments. Despite these differences, our projections show a maximum of 5% difference in total stand volume among treatments after 40 years.

Three 21-year-old Appalachian hardwood stands were strip cut using three cutting widths (2.4-m, 3.7-m, and 4.9-m) and allowed to resprout. One year after strip cutting, we examined the vegetation response within the harvested strips relative to non-treated control areas, focusing on the sprouting ability of young hardwood stems and the herbaceous component for wildlife habitat. Results indicate the width of the strip cutting significantly affected the amount of biomass produced from stump sprouts (p = 0.042) and influenced species composition. Shade-intolerant species accounted for more of the biomass production within the wider cut strip widths, while shade-tolerant and shade-intermediate species were more prominent within the narrower cut strips. Cut strip width did not have a significant effect on the biomass of new seedlings germinating after the cuttings. Herbaceous vegetation was greater within the 4.9-m cut strips than in the control plots (p = 0.046); however, the amount of herbaceous biom...

As southern pine forests (both planted and naturally regenerated) are more heavily used to provide biomass for the developing energy sectors and carbon sequestration, a better understanding of models used to characterize regional biomass estimates is needed. We harvested loblolly pines (Pinus taeda L.) between 0.5 and 15 cm dbh from several plantations and naturally regenerated stands in southeastern Arkansas to evaluate allometric relationships based on stand origin. In this process, each pine was separated into stemwood, branches + foliage, and taproot biomass components. Although the differences changed with dbh, loblolly pines from planted stands generally had greater percentages of biomass allocated to foliage + branches and taproots, whereas those from natural-origin stands had greater amounts in stemwood, aboveground, and total biomass. National Biomass Estimator (NBE) high-specific gravity pine equations predicted natural-origin aboveground biomass reasonably well. However, the same NBE model underpredicted aboveground biomass for small (similar to 5 cm) diameter planted pine and overpredicted planted pines between 7 and 15 cm dbh. When scaled to stand-level estimates, the NBE models resulted in estimates for average stand diameters of 5, 10, and 15 cm that ranged from -18.6 to 2.1% for natural stands and from -21.9 to 62.8% for planted stands. Agriculture and Food Research Initiative Competitive Grant from the USDA National Institute of Food and Agriculture [2009-35103-05356]; Southern Research Station of the USDA Forest Service; Arkansas Forest Resources Center We thank the following individuals for their contributions: Kirby Sneed and Rick Stagg (USDA Forest Service); Jonathan Hartley (University of Arkansas-Monticello); and Conner Fristoe (Weyerhaeuser Company). This research was supported by Agriculture and Food Research Initiative Competitive Grant 2009-35103-05356 from the USDA National Institute of Food and Agriculture, the Southern Research Station of the USDA Forest Service, and the Arkansas Forest Resources Center. Public domain – authored by a U.S. government employee

Temperate forests are extensive in the mid-latitudes of Earth and include a broad range of forest types and climates. Temperate forest soils reflect the seasonal variability in temperature and precipitation that make them productive and highly variable. Temperate forest soils also reflect the forest vegetation under which they develop. The extent, distribution and characteristics of temperate forests and forest soils are described in this Chapter, as well as their sensitivity to climate change. Because temperate forests are often located near large human populations, they are also affected by human intervention, such as pollution, management, introduction of pests and diseases, and local and national conservation policies. We consider the effects of changing temperature and precipitation regimes, and their interactions on temperate forest soils. Also, changes in frequency and severity of extreme events, as well as changes in length and timing of the growing seasons, can significantly affect the forests and forest soils.

This study assessed the effects of spacing and genotype on the growth and physiology of improved loblolly pine (Pinus taeda L.) seedlings from three distinct genotypes planted in Drew County, Arkansas (USA). Genotype had a significant effect on survival and height. Clone CF Var 1 showed greater height and survival compared to other seedlings. Genotype had significant effects on uniformity in height both years and ground line diameter (GLD) first year. However, genotype had no significant effects on leaf water potential and coefficient variation of leaf water potential. These growth and physiology should be further studied to assess potential genetic differences among seedlings and to determine if they can be identified early for improved growth at later ages.

Prescribed fire is used in the central Appalachians to promote and maintain mixed-oak and pine forests, create open forest conditions, improve habitat for wildlife, and to reduce the risk of impact of higher intensity wildfires on human development. Few studies have investigated responses of terrestrial salamander populations to habitat management using fire, and estimated responses have been neutral, negative, and positive depending on geography, species, and fire-severity. We examined woodland salamander (genus Plethodon) population responses to habitat management using prescribed fire on Shenandoah Mountain in the George Washington National Forest in West Virginia and Virginia, USA. We focused on responses of the Cow Knob Salamander (P. punctatus), a talus specialist and species of high conservation concern, but also examined responses of the Eastern Red-Backed Salamander (P. cinereus), a widespread habitat generalist. Three burn units were subjected to two low-severity burns and one unit was burned five times with ca. 40% tree mortality. Using a combination of nighttime visual encounter surveys and coverboard surveys, we compared terrestrial salamander abundance and body condition in unburned and burned areas. We also measured habitat characteristics at sampling sites to determine if prescribed burn histories were correlated with habitat conditions important to woodland salamanders. Mean abundance for P. punctatus was lower at sites that were burned, but there was not a strong burn effect for P. cinereus. Abundance of both species was positively correlated with canopy cover. Mean and median body condition index (BCI) score was higher for P. punctatus and lower for P. cinereus on the West Virginia side of Shenandoah Mountain, and lower in burned areas for both species. However, the most parsimonious BCI models did not contain the burn predictor. Management using prescribed fire altered microhabitat conditions that are important for woodland salamanders, such as canopy cover, leaf litter depth, and vegetation groundcover. Our study suggests that woodland salamanders in the central Appalachians can persist in forests managed using prescribed fire, but also indicates that prescribed fire can result in reduced habitat quality for some woodland salamander species.

A mixed-integer linear programming model was developed to optimize the multiple biomass feedstock supply chains, including feedstock establishment, harvest, storage, transportation, and preprocessing. The model was applied for analyses of multiple biomass feedstocks at county level for 13 states in the northeastern United States. In the base case with a demand of 180,000 dry Mg/year of biomass, the delivered costs ranged from $67.90 to $86.97 per dry Mg with an average of $79.58/dry Mg. The biomass delivered costs by county were from $67.90 to 150.81 per dry Mg across the northeastern U.S. Considered the entire study area, the delivered cost averaged $85.30/dry Mg for forest residues, $84.47/dry Mg for hybrid willow, $99.68 for switchgrass and $97.87 per dry Mg for Miscanthus. Seventy seven out of 387 counties could be able to deliver biomass at $84 per dry Mg or less a target set by US DOE by 2022. A sensitivity analysis was also conducted to evaluate the effects of feedstock availability, feedstock price, moisture content, procurement radius, and facility demand on the delivered cost. Our results showed that procurement radius, facility capacity, and forest residue availability were the most sensitive factors affecting the biomass delivered costs.

Large-scale planted forests (PF) have been given a higher priority in China for improving the environment and mitigating climate change relative to natural forests (NF). However, the ecological consequences of these PF on water resource security have been less considered in the national scale. Moreover, a critically needed comparison on key ecological effects between PF and NF under climate change has rarely been conducted. Here, we compare carbon sequestration and water consumption in PF and NF across China using combination of remote sensing and field inventory. We found that, on average, NF consumed 6.8% (37.5 mm per growing season) less water but sequestered 1.1% (12.5 g C m-2 growing season-1 ) more carbon than PF in the period of 2000-2012. While there was no significant difference in water consumption (p = 0.6) between PF and NF in energy-limited areas (dryness index [DI] 1). Moreover, a distinct and larger shift of water yield was identified in PF than in NF from the 1980s to the 2000s, indicating that PF were more sensitive to climate change, leading to a higher water consumption when compared with NF. Our results suggest NF should be properly valued in terms of maximizing the benefits of carbon sequestration and water yield. Future forest plantation projects should be planned with caution, particularly in water-limited regions where they might have less positive effect on carbon sequestration but lead to significant water yield reduction.

Eastern cottonwood (Populus deltoides Bartr. ex Marsh.) is commonly propagated using un-rooted cuttings. While cutting length and diameter, genetics and environmental conditions are often cited as major factors contributing to the successful establishment of cottonwood plantations, it is difficult to determine which specific cutting characteristic or mechanism leads to improved root establishment or plant development. For example, increasing stem size can affect rooting and subsequent plant growth by altering the cutting energy reserves as well as the surface area from which latent roots develop. In this study, the contribution of cutting length and belowground surface area to rooting and early growth was examined for eastern cottonwood. To discern cutting length effects, the belowground portion of four different cutting lengths was restricted so each cutting had the same belowground surface area available for rooting. To discern surface area effects, 40-cm-long cuttings were restricted to produce four different levels of surface area from which roots could develop. Leaf area, stem height, aboveground and belowground biomass, and root numbers were measured after 13 weeks of growth. The only statistically significant relationships related to biomass were due to the initial differences in cutting length. Cuttings with greater surface areas formed more lateral roots, while longer cuttings did not. By contrast, increased cutting lengths resulted in greater numbers of basal roots, but not for cuttings with greater belowground surface areas.

Loblolly pine (Pinus taeda L.), silver maple (Acer saccharinum L.), and cottonwood (Populus deltoides Bartr.) are short-rotation woody crops with potential use for biomass plantations. The study of fine-root production and mortality in these intensively managed crops is important to understand carbon and nutrient cycling in these systems. We used minirhizotrons to measure monthly fine-root production and mortality of each species in a biomass plantation during the second growing season in Collins, Arkansas, USA. Images were taken and digitized on a monthly basis from March 2008 to February 2009 to calculate volumes and were converted into dry-weight biomass. Data analysis showed that net fine-root production varied among the species and the time of year. Loblolly pine had significantly greater net fine-root production and mortality than others. Overall fine-root production was greatest during fall months, whereas fine-root mortality showed no seasonal difference.

Fine-root production was studied in recently established loblolly pine (Pinus taeda), silver maple (Acer saccharinum), and cottonwood (Populus deltoides) biomass plantations. Dry weights of fine roots produced in ingrowth cores were recorded from April 2008 to March 2009 to quantify the temporal variation of fine-root production among the species. Similarly, fine-root production was compared to the monthly height and diameter increments, soil temperature, and moisture content. Species showed no significant difference in fine-root production; however, fine-root production varied by month. Fine-root production in September was significantly different from that of December and January combined, February, and May. Loblolly pine produced 49 g m−2, whereas silver maple and cottonwood produced 37 g m−2 and 35 g m−2 of fine roots, respectively, during the study period. Fine-root production was not correlated with height increment, diameter increment, soil temperature, and soil moisture.

The limited success of methods to naturally regenerate northern red oak (Quercus rubra L.) has increased the use of artificial techniques to improve overall oak composition. Enrichment plantings are often recommended as a means to supplement species composition within the existing natural reproduction. Previous enrichment efforts have often resulted in low survival and poor growth, generally due to poor planting stock quality and a lack of competition control. In this study, high quality northern red oak seedlings were established on four recently harvested sites in western North Carolina using one of four competition control treatments (untreated, year 1 control, year 2 control or a weed mat) in a 1.2 × 1.2 m area around each seedling with or without a soil fertility amendment. The 3 year results show that competition control and fertilization treatments had few positive impacts on survival and growth of the planted seedlings. These results suggest that either the treatment area was insufficient to adequately release the seedlings, or other factors like belowground competition from existing advance reproduction and/or stump sprouts may be important determinants of the overall success of northern red oak enrichment plantings on recently harvested sites.

Yellow-poplar (Liriodendron tulipifera L.) is one of the more commonly regenerated species in upland Piedmont stands following clearcut reproduction methods. Recent studies show that a variety of silvicultural activities affect the growth of yellow-poplar seedlings. However, the factors responsible for these changes in growth have not been documented in detail. Weed control, fertilization and thinning treatments were imposed on rising 1- and 3-year-old naturally regenerated stands. Stem growth and monthly height growth patterns, and leaf physical and chemical parameters were compared by treatment during the third growing season after treatments were initiated. The response of yellow-poplar to fertilization suggests that inherent site resources are not suitable for optimal growth, especially when stem densities are high. Vector analysis of N, P and K responses to fertilization, weeding and thinning treatments demonstrated that yellow-poplar responded to ameliorations of N and P deficiencies. Thinned + weeded yellow-poplar, with or without fertilization, had a greater percentage of height growth later in the summer compared to other treatments. Foliar characteristics like leaf number, leaf size and nitrogen concentration were positively correlated with stem growth. The largest increases in leaf area were coincident with increases in foliar N and P.

Intense competition for growth resources between herbaceous and woody vegetation is considered a major constraint to the growth and development of newly regenerated forest stands. However, very few studies have explored silvicultural opportunities to manage these constraints. In this study, the effects of fertilization, density and vegetation control on rising 1- and 3-year-old upland mixed species NC Piedmont stands were monitored for 3 years following the imposition of treatments. Broadcast fertilization proved very beneficial in accelerating stem growth and promoting self-thinning at both sites. Weeding (non-arborescent vegetation) treatments without thinning had no effect on stem height. At both sites, substantial increases in tree size were noted for yellow-poplar and oaks when thinning and weeding treatments were combined. A significant fertilization effect on thinned plots was also noted for oaks. These results demonstrate that stem growth and stand development are constrained by the availability of site growth resources, and can be silviculturally managed to promote stand development.

Successful establishment of hardwood plantations requires effective weed management. Mechanical weed control is inefficient, and few herbicides are available for use in hardwood plantations. In an effort to identify new chemical control options, the potential of imazapyr (Chopper herbicide) for site preparation prior to planting three common southern hardwood species was assessed. Twelve site preparation treatments were tested using Chopper applied at four rates and three timings prior to planting. Each site preparation rate and time pairing was repeated under two postplant herbicide regimes—directed glyphosate (Accord herbicide) sprays designed to maintain weed-free conditions and a single broadcast sulfometuron methyl (Oust herbicide) treatment designed to test a potential operational sequencing of Chopper site preparation followed by herbaceous weed control. Although results must be evaluated in the context of a single site and set of environmental conditions, they demonstrate the utility of Chopper herbicide for site preparation prior to planting hardwoods. For sycamore (Platanus occidentalis L.)and sweetgum (Liquidambar styraciflua L.),site preparation before the end of July with Chopper rates up to 64 oz/ac improved survival and growth over postplant treatments alone. For later season applications, sycamore and sweetgum were more sensitive to the Chopper site preparation rate. For Oct. site preparation, Chopper rates above 16 oz/ac adversely affected planted sycamore seedlings and rates greater than 32 oz/ac adversely effected planted sweetgum seedlings. Cherrybark oak (Quercus pagoda Raf.)performed best using the highest Chopper rate of 64 oz/ac regardless of timing. South. J. Appl. For. 28(3):163–170.

Forty-two forestry best management practices (BMPs) were assessed to determine the extent of voluntary application and their effectiveness in preventing water quality impacts in New York State. These BMPs were evaluated on 61 timber-harvested sites in the Catskill region (CR), and 53 timber harvested sites in the Adirondack region (AR) during the summers of 1997 and 1998. The overall application of suggested BMPs was 78% for haul roads, 87% for landings, 59% for skid trails, 88% for equipment maintenance/operation, and 73% for buffer strips. Departures were common for BMPs concerned with draining water off haul roads and skid trails, and for stream crossings; more attention must be devoted to those practices. Effectiveness of BMPs was apparent when they were applied. Nonparametric statistical tests showed a strong relationship between BMP application and prevention of sediment movement. Limiting sediment movement protects surface water. In the CR, 27 of the 33 BMPs tested showed a statistically significant (P < 0.10) relationship between BMP application and sediment movement. Similar results were observed in the AR; 26 of the BMPs tested were significantly associated with sediment movement. Imperfect application of BMPs reduced effectiveness. Road drainage structures, for example, generally failed to adequately control erosion when spacing between drainage structures was excessive. North. J. Appl. For. 17(4): 125–134.