Browsing by Author "Bolding, M. Chad"
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- An Analysis of Log Truck Turn Times at Harvest Sites and Mill FacilitiesDowling, Tripp N. (Virginia Tech, 2010-04-19)The raw forest products transportation sector is inherently unique when compared to other transportation industries. The loggers and contractors who transport raw forest products are at a competitive disadvantage. Older equipment is also commonly used by the raw forest products transportation industry in harsh working environments. The average log truck age is 9.7 years while all trucks average only 3.9 years. Nineteen percent of log trucks are 15 years old or older while only 5.9% of all trucks are older than 8 years. Log trucks are regulated by both the Federal Motor Carrier Safety Administration and the state that the truck operates in, thus making interstate transportation more difficult. In addition to these challenges, there is a lack of information concerning efficiency and productivity improvement opportunities related to transporting forest products. This study evaluated truck turn times at both the harvesting site and mill facilities in order to identify important trucking productivity factors and efficiency improvement opportunities. Regression equations were created to estimate truck turn times at harvesting sites and mill facilities. Gross level studies found that 1268 truck turns at the tract scale averaged 1.40 hours while 576 truck turns at the mill scale averaged 0.56 hours. Elemental time studies at four harvesting locations found that log trucks were idle 32% of the time. Trucks spent 29% of time being loaded and 26% of the time waiting. Elemental time studies at mill facilities found that trucks were idle 27% of the time. Trucks spent the greatest amount of time unloading while unbinding was the second greatest contributor to turn times. Reductions in loading and waiting times can have significant effects on the overall turn time. Harvesting contractors could benefit from maintaining balanced harvesting crews. Estimates indicate that harvesting contractors could earn an additional profit of $106,500 over a period of five years by purchasing an additional skidder for those crews whose production is limited due to a lack of skidding capacity. It is estimated that if adding an additional trailer to harvesting crews would allow an additional 2 loads to be transported to the mill each day, harvesting crews could earn an additional $22,100 per year of profit. Road construction can also affect harvesting contractors profits. By minimizing road construction through the use of easements and improved pre-harvest planning, harvesting contractors could reduce road construction costs by as much as $14,000 per tract. With tools available to estimate truck turn around times, harvesting contractors, fleet managers, and truck drivers will be able to make more informed decisions regarding fleet management. This will enable those owning and operating trucks to operate in more efficient and profitable manners. The models created during this study will allow managers to estimate tract and mill turn times so as to better allocate trucking resources.
- Anticipated Impact of a Vibrant Wood-to-Energy Market on the U.S. South's Wood Supply ChainConrad, Joseph Locke IV (Virginia Tech, 2011-08-11)Recent emphasis on producing energy from woody biomass has raised questions about the impact of a vibrant wood-to-energy market on the southern wood supply chain, which consists of forest landowners, forest industry mills, and harvesting contractors. This study utilized two surveys of southern wood supply chain participants and a designed operational study of an energywood harvest to investigate the impact of an expanded wood-to-energy market on each member of the southern wood supply chain. First, a survey of consulting foresters was conducted to examine how harvest tract size, forest ownership, and forest industry structure have changed within the U.S. South and how foresters expect the wood-to-energy market to impact the wood supply chain in the future. Second, this study employed a mail survey of forest landowners, forest industry mills, and wood-to-energy facilities from the thirteen southern states in order to investigate expected competition for resources, wood supply chain profitability, and landowner willingness to sell timber to energy facilities. Third, this study conducted a designed operational study on a southern pine clearcut in the Coastal Plain of North Carolina, with three replications of three harvest prescriptions to measure harvesting productivity and costs when harvesting woody biomass for energy. The three treatments were: a Conventional roundwood only harvest (control), an Integrated harvest in which roundwood was delivered to traditional mills and residuals were chipped for energy, and a Chip harvest in which all stems were chipped for energy use. Results from the two surveys suggest that timber markets are inadequate in many areas of the South as a result of expanded timber supply and reduced forest products industry capacity. Only 12% of responding landowners and foresters had sold wood to an energy facility, indicating that wood-to-energy markets are non-existent in many areas of the South. Nonetheless, 98% of consulting foresters and 90% of landowners reported a willingness to sell timber to an energy facility if the right price were offered. Consulting foresters expected wood-to-energy facilities to provide an additional market for wood, and not displace forest products industry capacity. However, two-thirds of consulting foresters, wood-to-energy facilities, and private landowners expected competition between mills and energy facilities while 95% of fibermills (pulp/paper and composite mills) expected competition. Fibermills were much more concerned about competition for resources and increases in wood costs than any other member of the southern wood supply chain. The operational study documented the challenges facing some harvesting contractors in economically producing energywood. Onboard truck roundwood costs increased from $9.35 green t-1 in the Conventional treatment to $10.98 green t-1 in the Integrated treatment as a result of reduced felling and skidding productivity. Energy chips were produced for $19.19 green t-1 onboard truck in the Integrated treatment and $17.93 green t-1 in the Chip treatment. Energywood harvesting costs were higher in this study than in previous research that employed loggers with less expensive, more fuel efficient equipment. This suggests that high capacity, wet-site capable loggers may not be able to economically harvest and transport energywood without a substantial increase in energywood prices. This study suggests that the southern wood supply chain is in position to benefit from a vibrant wood-to-energy market. Landowners should benefit from an additional market for small-diameter stems. This study shows that high production, wet-site capable loggers should not harvest energywood until prices for this material appreciate considerably. Wet-site loggers have very expensive equipment with high hourly fuel consumption rates and this study documented that energywood production was not sufficiently high to offset the high hourly cost of owning and operating this equipment. Nevertheless, a wood-to-energy market should benefit harvesting contractors in general because unless the forest products industry contracts further, loggers can continue to harvest and deliver roundwood to mills as they do at present and those properly equipped for energywood harvesting at low cost may be able to profit from a new market. The forest products industry has the largest potential downside of any member of the southern wood supply chain. This study documents widespread anticipation of competition between the forest products and wood-to-energy industries. However, to date there has been minimal wide-scale competition between the forest products and wood-to-energy industries. It is possible that the wood-to-energy industry will complement, rather than compete with the forest products industry, and thereby benefit each member of the southern wood supply chain.
- Biomass Harvesting Effects on Soil Physical Properties in the Coastal Plain of North CarolinaChandler, Josh (Virginia Tech, 2011-11-11)Biomass harvesting offers opportunities to produce portions of US energy demands from renewable resources, yet there are concerns that biomass harvesting could deplete nutrient reserves, increase potential for soil erosion, or lead to problems associated with increased forest trafficking. On intensively managed loblolly pine (Pinus taeda) plantations on relatively flat coastal plain terrain, nutrient demands may be met with fertilization and soil erosion is of lower concern. However, soil disturbance associated specifically with coastal plain biomass harvests for renewable energy production have not been widely documented. Soil disturbance classes and physical properties were examined on three intensities of biomass harvesting on a 52 ha loblolly pine plantation in the North Carolina coastal plain. Study objectives were to determine if biomass harvesting intensity and associated traffic were correlated with changes in soil physical properties or visual soil disturbance classifications. Harvesting intensities included in the designed operational study were: 1) roundwood removal only, 2) integrated harvest including roundwood removal and biomass production, and 3) chip only harvest where all trees were removed and chipped for biomass. Harvesting treatments were replicated 3 times each (9 experimental units) using a randomized complete block design. Soil properties were evaluated pre- and post-harvest to determine harvesting related impacts. Results indicate that most soil physical properties were not significantly altered due to harvest level with the exception of small deck areas. These data indicate that biomass harvesting did not result in visual or physical changes to soil properties as compared to traditional harvests and indicate that standard best management practices may be adequate to address biomass harvesting issues for similar sites.
- Characteristics of Logging Businesses across Virginia’s Diverse Physiographic RegionsBarrett, Scott M.; Bolding, M. Chad; Munsell, John F. (MDPI, 2017-11-28)Logging businesses play an important role in implementing forest management plans and delivering the raw material needed by forest products mills. Understanding the characteristics of the logging workforce can help forest managers make better decisions related to harvesting operations. We surveyed logging business owners across Virginia’s three physiographic regions (Mountains, Piedmont, and Coastal Plain). Overall, logging businesses reported an average production rate of 761.37 t/business/week, but this varied substantially by region, with the highest production rates in the Coastal Plain (1403.55 t/business/week), followed by the Piedmont (824.69 t/business/week) and the Mountains (245.42 t/business/week). Many operations in the Mountains rely primarily on manual felling (66.6% of respondents) and these operations often have lower production rates. Across all regions, 81.7% of reported production came from operations that primarily utilized rubber-tired feller-bunchers for felling. Logging businesses were sorted based on reported production capacity and then divided into three groups (high, medium, and low production) based on total reported production. Across all regions, the majority of reported production was produced by the high production logging businesses. This was highest in the Piedmont, where the high production businesses accounted for 74.8% of total reported production.
- Comparing Sediment Trap Data With Erosion Models for Evaluation of Forest Haul Road Stream Crossing ApproachesLang, A. J.; Aust, W. Michael; Bolding, M. Chad; McGuire, Kevin J.; Schilling, Erik B. (American Society of Agricultural & Biological Engineers, 2017-01-01)Soil erosion and sediment delivery models have been developed to estimate the inherent complexities of soil erosion, but most models are not specifically modified for forest operation applications. Three erosion models, the Universal Soil Loss Equation for forestry (USLE-Forest), Revised Universal Soil Loss Equation Version 2 (RUSLE2), and Water Erosion Prediction Project (WEPP), were compared to one year of trapped sediment data for 37 forest haul road stream crossings. We assessed model performance from five variations of the three erosion models: USLE-Roadway, USLE-Soil Survey, RUSLE2, WEPP-Default, and WEPP-Modified. Each road approach was categorized into one of four levels of erosion (very low, low, moderate, and high) based on trapped erosion rate data and erosion rates reported in recent peerreviewed literature. Model performance metrics included: (1) summary statistics and nonparametric analysis, (2) linear relationships, (3) percent agreement within erosion categories and tolerable error ranges, and (4) contingency table metrics. Sediment trap data varied from negligible (<0.1) to hundreds of Mg ha-1 year-1. The soil erosion models evaluated could estimate erosion within 5 Mg ha-1year-1 for most approaches having erosion rates less than 11.2 Mg ha-1 year-1, while models estimates varied widely for approaches that eroded at rates above 11.2 Mg ha-1year-1. Kruskal-Wallis nonparametric analyses revealed that only WEPP-Modified estimates were not significantly different from trapped sediment data (p ≥ 0.107). While WEPP-Modified ranked best for most model performance metrics, the time, effort, modeling expertise, and uncertainty associated with model results may discourage the use of WEPP as a forest management tool. WEPP is better suited for researchers and government agencies that have the capability to measure extensive parameter data. Additional sensitivity analysis is needed to expand default parameters for forest roads within the WEPP and USLE models.
- Comparing sediment trap data with the USLE-forest, RUSLE2, and WEPP-road erosion models for evaluation of bladed skid trail BMPsWade, Charles R.; Bolding, M. Chad; Aust, W. Michael; Lakel, William A.; Schilling, Erik B. (American Society of Agricultural and Biological Engineers, 2012)Three erosion models, the Universal Soil Loss Equation for Forestry (USLE-Forest), the Revised Universal Soil Loss Equation Version 2 (RUSLE2), and the Water Erosion Prediction Project for Forest Roads (WEPP-Road), were compared to sediment trap data for bladed skid trail best management practices (BMPs). The bladed skid trail BMPs evaluated were: (1) water bar only (control treatment); (2) water bar + lime, fertilizer, and grass seed (seed treatment); (3) seed + straw mulch (mulch treatment); (4) control + piled hardwood slash (hardwood slash treatment); and (5) control + piled pine slash (pine slash treatment). This study used three erosion models to evaluate the BMPs while also using linear regression, model efficiency (NSE), and percent bias (PBIAS) to compare the prediction accuracy and applicability of the models to monthly erosion collected in sediment traps from six replications of the five treatments. Results showed significant treatment differences due to the BMPs, with the control treatment being the most erosive, followed generally by the seed, hardwood slash, pine slash, and mulch treatments. Model predictions indicated that all models were suitable for ranking erosion rates for the skid trail closure treatments for simple hazard or BMP ratings. However, the older and simpler USLE-Forest and RUSLE2 models had satisfactory NSE and PBIAS values, whereas WEPP-Road did not. Results indicate that WEPP-Road needs additional enhancement with regard to skid trail parameters before it can be effectively used for erosion prediction on bladed skid trails.
- A Comparison of Chipper Productivity, Chip Characteristics, and Nutrient Removals from Two Woody Biomass Harvesting TreatmentsGroover, Miles Clark (Virginia Tech, 2011-11-30)Increased costs of fossil fuels, regulatory policies, and investments by federal and state governments have caused increased interest and incentive for the use of wood as a renewable form of energy. As a result, landowners and forest managers are considering chipping whole trees and harvesting residues as a means to meet increased demand of wood chips as a renewable source of energy. However, the profitability, productivity gains, and sustainability of these alternative harvesting methods continue to be an area of research. The objective of this study was to compare two biomass harvesting treatments with regard to the characteristics of the chips they produced, chipper productivity, nutrient removals, and site disturbance. The first biomass harvesting treatment was an integrated harvest where roundwood was merchandized and hauled to the appropriate mill and limbs, tops, and small stems (residues) were chipped for hog fuel. The second biomass harvesting treatment simulated a scenario where biomass markets were competing with pulpwood markets and landowners could choose to sell wood for energy or pulp wood. In this treatment whole trees and small stems were chipped for hog fuel. A third harvesting treatment was a conventional roundwood harvest where no wood was chipped, and this treatment was used as a control for comparison of nutrient removals and site disturbance. The chips produced from both harvesting treatments were very similar, but those produced from whole trees tended to be slightly smaller than those produced from residues. Chipper productivity was significantly higher when chipping whole trees and it was also much more efficient in terms of fuel use. Estimations of nutrient removals showed that there was very little difference in the amount of nutrient removed from the biomass harvesting treatments, but both treatments removed significantly more N and Ca than the conventional roundwood harvesting treatment. There was significantly more downed and standing material left on the site after harvesting in the conventional treatment, but this did not translate into a large amount of additional nutrients left on the site. There was little difference in soil disturbance between all three treatments, and due to the dry soil conditions during harvesting, there was very little visual soil disturbance at all during harvesting.
- Consider Logging Residue Needs for BMP Implementation When Harvesting Biomass for EnergyBarrett, Scott M.; Aust, W. Michael; Bolding, M. Chad (Virginia Cooperative Extension, 2014-08-07)This publication reviews the Best Management Practices (BMP) on harvesting forestry operations particularly when harvesting biomass.
- Consider logging residue needs for BMP implementation when harvesting biomass for energyBarrett, Scott M.; Aust, W. Michael; Bolding, M. Chad (Virginia Cooperative Extension, 2019)Logging residues for Best Management Practices. Residue can be used for slash or for water protection.
- Differing Levels of Forestry Best Management Practices at Stream Crossing Structures Affect Sediment Delivery and Installation CostsMorris, Brian C.; Bolding, M. Chad; Aust, W. Michael; McGuire, Kevin J.; Schilling, Erik B.; Sullivan, Jay (MDPI, 2016-03-10)Forestry best management practices (BMPs) are used to reduce sedimentation from forest streamcrossings. Three BMP treatments (BMP, BMP-std, and BMP+) were applied to three forest road stream crossings (bridge, culvert, and ford). BMP did not meet existing BMP guidelines, BMP-std met standard recommendations, and BMP+ treatments exceeded recommendations. Following BMP applications, three simulated rainfall intensities (low, medium, and high) were applied in order to evaluate sediment delivery from crossing type and BMP level. During rainfall simulation, sediment concentrations (mg/L) were collected with automated samplers and discharge (L/s) was estimated to calculate total sediment loading. Costs of stream crossings and BMP levels were also quantified. Mean sediment associated with the three stream crossings were 3.38, 1.87, and 0.64 Mg for the BMP, BMP-std, and BMP+ levels, respectively. Ford, culvert, and bridge crossings produced 13.04, 12.95, and 0.17 Mg of sediment during construction, respectively. BMP enhancement was more critical for sediment control at the culvert and ford crossings than at the bridge. Respective costs for BMP , BMP-std, and BMP+ levels were $5,368, $5,658, and $5,858 for the bridge; $3,568, $4,166 and $4,595 for the culvert; and $180, $420 and $1,903 for the ford. Costs and sediment values suggest that current standard BMP levels effectively reduce stream sediment while minimizing costs.
- Effectiveness of skid trail closure techniques forest operations research highlightsBarrett, Scott M.; Aust, W. Michael; Bolding, M. Chad (Virginia Cooperative Extension, 2019)Overland skid trails produce less erosion than bladed skid trails because they retained more ground cover. Slopes produced 82% less erosion than the bladed skid trails.
- Effectiveness of Skid Trail Closure Techniques. Forest Operations Research HighlightsBarrett, Scott M.; Aust, W. Michael; Bolding, M. Chad (Virginia Cooperative Extension, 2014-08-07)Best Management Practices (BMP) guidelines offer multiple possible options for practices to minimize erosion and sedimentation and protect water quality. This research focused on evaluating post-harvest erosion from skid trails with different closure methods.
- Effectiveness of State Developed and Implemented Forestry Best Management Practices in the United StatesCristan, Richard (Virginia Tech, 2016-06-28)The passage of the Federal Water Pollution Control Act of 1972 required states to develop forestry BMPs to help reduce potential nonpoint source pollution from forest operations. Properly applied forestry best management practices (BMPs) have since been proven to protect water quality from forest operations. This research project reviewed BMP effectiveness studies in the U.S., assessed current state developed and implemented of forestry BMPs, and developed a simple method to estimate potential erosion from forest operations for the Piedmont physiographic region based on previous studies. Eighty-one BMP effectiveness studies were reviewed. The review of past effectiveness studies indicates that water quality protection is increased when BMPs are implemented correctly. These effectiveness studies provide states with valuable information on how their BMP guidelines are achieving the goals defined by the Federal Water Pollution Control Act. Every U.S. state has forestry BMP guidelines. These guidelines may be non-regulatory, quasi-regulatory, or regulatory depending on the state. Twenty states reported implementing non-regulatory BMP guidelines, 19 quasi-regulatory BMP guidelines, and 11 regulatory BMP guidelines. State forestry agencies were reported as being the lead agency responsible for BMP monitoring in 35 states. The national forestry BMP implementation rate was 91% (32 states). However, states did report deficiencies for specific BMP guideline categories. Supplementary to the reviewed BMP effectiveness studies, forest erosion studies in the southeastern U.S. that quantified erosion rates from forest operations were also reviewed. Erosion rates obtained from the literature were reviewed by operation categories (timber harvesting, forest roads, skid trails, log landings, stream crossings, and streamside management zones) and physiographic region (Mountains, Piedmont, Gulf Coastal Plain, and Atlantic Coastal Plain). There were numerous research gaps regarding erosion rates from forest operations for all the regions except the Piedmont region. The Piedmont region was selected for developing a method to estimate potential erosion from forest operations. This erosion estimation method is a quick and potentially useful tool for estimating potential erosion; however, it is based on limited data from the Piedmont region only. The basic method approach might be considered for the other physiographic regions, but further research is needed to fill current knowledge gaps.
- Effectiveness of Temporary Stream Crossing Closure Techniques Forest Operations Research HighlightsBarrett, Scott M.; Aust, W. Michael; Bolding, M. Chad (Virginia Cooperative Extension, 2014-08-08)The focus of Virginia's silvicultural water quality law is prevention of sedimentation, so stream crossings are an area where proper closure and stabilization are critical. This research focused on evaluating sedimentation in streams as a result of three different options for temporary stream crossing closure Best Management Practices (BMPs).
- Effectiveness of temporary stream crossing closure techniques. Forest operations research highlightsBarrett, Scott M.; Aust, W. Michael; Bolding, M. Chad (Virginia Cooperative Extension, 2019)Slash was the most cost effective of the treatments. When slash is applied as a part of the harvesting operation it can be effective at reducing sediment and is the most cost effective treatment
- Effectiveness, cost, and implications of forest haul road stream crossing structures and best management practices in VirginiaMorris, Brian C. (Virginia Tech, 2015-07-06)Forest roads and stream crossings have the potential to be sources of sediment from forest operations. Recent litigation has renewed interest in furthering research related to forest road Best Management Practices (BMPs). Three legacy (100 year old) forest road stream crossings were monitored for suspended sediment for nine months before and six months after upgrading three unimproved ford crossings with one bridge, one culvert, and one improved ford. During construction, rainfall simulation was utilized to estimate the sediment contribution of each crossing with minimal BMPs (BMP-), BMPs equal to state recommendations (BMP), and BMPs beyond state recommendations (BMP+). Construction costs were recorded to quantify the change in cost with a change in BMP level. Three levels of rainfall simulation were used on each BMP treatment for each crossing resulting in 27 rainfall simulations. Water samples collected by an automatic sampler downstream of the crossings were analyzed for suspended sediment. Pre - and post- construction time periods were compared to assess how the improved crossings altered total suspended sediment concentrations downstream of the crossings. The number of stream crossings constructed per year in Virginia was also estimated using satellite imagery on 400 harvest tracts. Site visits were conducted on 240 harvest tracts where data were collected on the presence of crossings, the types of crossings, and the level of BMP implementation. Rainfall simulation experiments showed decreased sediment with increased BMP level and daily total suspended sediment concentrations measured over 15 months showed a decrease in mean daily sediment concentration after construction of the bridge and culvert crossings. There was no decrease in sediment concentration for the ford crossing. Statewide crossing construction and BMP implementation rates were estimated. Approximately 67% of the audited stream crossings were characterized as having BMPs that were equal to or beyond state recommendations. Increased BMPs and upgrading of stream crossings resulted in decreased total suspended sediment. However, increased BMP implementation also increased stream crossing construction costs. Effectiveness of increased levels of BMPs and the pre and post construction analysis suggests the improvement of a legacy stream crossing may reduce total suspended sediment concentrations.
- Efficacy of operational stream crossing best management practices on truck roads and skid trails in the Mountains, Piedmont, and Coastal Plain of VirginiaDangle, Chandler Lipham (Virginia Tech, 2018-06-08)Forestry best management practices (BMPs) programs were developed by individual states in response to the Clean Water Act in order to protect water quality during and after timber harvests. Our research goals are to compare BMP implementation at stream crossings by region and road type in Virginia and to quantify effectiveness of BMPs by developing hypothetical upgrades and determining upgrade costs. Stream crossings (75 truck, 79 skidder) sampled for BMP implementation were on operational harvests conducted in 2016, from the Mountains, Piedmont, and Coastal Plain of Virginia. Erosion rates of stream crossing approaches were modeled using the Universal Soil Loss Equation modified for forest lands (USLE-Forest) and Water Erosion Prediction Project (WEPP) methodologies. Implementation ratings (BMP-, BMP-standard, BMP+) were developed to characterize crossings with respect to state implementation standards. Costs for upgrading crossings to a higher BMP category were estimated by adjusting cover percentages and approach lengths. Sixty-three percent of stream crossings were classified as BMP-standard, with an average erosion rate of 7.6 Mg/ha/yr; 25% of crossings were classified as BMP+, with an average erosion rate of 1.7 Mg/ha/yr; and 12% of crossings were classified as BMP-, with an average erosion rate of 26.2 Mg/ha/yr. Potential erosion rates decreased with increasing BMP implementation (p <0.0001). Average BMP implementation audit scores for stream crossings were 88% on skid trails and 82% on truck roads. To upgrade from a BMP- to BMP-standard, the cost-benefit ratio of dollars to tons of sediment prevented averaged $166.62/Mg for skid trails and $2274.22/Mg for truck roads. Enhancement to the BMP+ level is not economically efficient and BMP implementation at stream crossings reaches maximum efficiency at the BMP-standard level.
- Estimated Sediment Protection Efficiences for Increasing Levels of Best Management Practices on Forest Harvests in the Piedmont, USACristan, Richard; Aust, W. Michael; Bolding, M. Chad; Barrett, Scott M. (MDPI, 2019-11-07)In-stream watershed level evaluations confirm that application of recommended forestry best management practices (BMPs) can minimize sedimentation following management, while on-site erosion research shows that BMPs reduce erosion from individual forest operations, thus implying watershed-level sediment reductions. Assessments of forest operations and sediment have developed very few sediment delivery ratios (SDR). Linking BMP levels (low, standard recommendation, high) within specific forest operations to sedimentation could enable managers to evaluate BMP effects. Reported data regarding forest operations, erosion rates and SDR by forest operation, and BMP implementation levels were sufficient within the Piedmont region to allow approximations of sediment delivery and BMP efficiency. Existing United States Department of Agriculture (USDA) Forest Service reports and published erosion and sediment research were used to comprise the following method. For regional annual harvests, estimated sediment deliveries (Mg year−1) = annual harvest area (ha year−1) × weighted average erosion rate from all forest operations (Mg ha−1 year−1) × SDR (unitless ratio). Weighted average erosion rates for all forest operations were determined by applying areas in each operational activity (%) × estimated erosion per operation (Mg ha−1 year−1). In comparing published data, standard BMPs reduced estimated sedimentation by 75% compared to low BMP implementation levels. This supports forestry BMP efficiency findings reported for sediment removals in watershed studies. Higher levels of BMP implementation were estimated to potentially remove nearly all forest operation-produced sediment. Values of this pilot study should be viewed cautiously, as estimates were based on limited data, estimated operations, and limited SDRs; are based on BMP categories that vary between states; and address only one year following harvests. However, the approach provided approximations that facilitate BMP evaluations and can be improved with additional data. This methodology highlights the importance of accurate estimates of erosion rates, SDRs, sediment masses, and area for operations. This supports the importance of state programs, which have increased BMP implementation rates and compliance options with BMP program maturation.
- Estimating Costs and Effectiveness of Upgrades in Forestry Best Management Practices for Stream CrossingsNolan, Lindsay; Aust, W. Michael; Barrett, Scott M.; Bolding, M. Chad; Brown, Kristopher; McGuire, Kevin J. (MDPI, 2015-12-08)Forestry Best Management Practices (BMPs) are used for protection of water quality at forest stream crossings, yet effects and costs for gradients of BMPs are not well documented. We evaluated forty-two truck road and skid trail stream crossings using three surrogates of BMP adequacy: (1) potential erosion rates for stream crossing approaches; (2) adequacy of stream crossing BMPs; and (3) overall BMP rating (BMP−, BMP-standard, and BMP+). Subsequently, BMP upgrades were recommended for enhancing BMP− or BMP-standard stream crossings. Costs for BMP upgrades were estimated using an existing road and skid trail cost method. The majority of truck road stream crossings were culverts, while skid trail stream crossings were primarily portable bridges. Potential erosion estimates, BMP audit scores, and BMP ratings all indicated that skid crossings have lower BMP implementation than truck road crossings. BMP improvements commonly identified for skid trail and truck crossings included addition of cover and water control structures. Improved BMPs at skid trail crossings were less expensive than those at truck road crossings. Current BMP guidelines provide economical and effective techniques for reducing erosion, and BMP upgrades have the potential to reduce erosion rates to similar levels found in undisturbed forests.
- Evaluating Energywood Harvesting Operations in The Lower Mid-Atlantic Region of the United StatesGarren, Austin Mack (Virginia Tech, 2022-04-12)Increased markets for renewable energy feedstocks have led to increased energywood production in the Southeastern United States. Energywood requires additional processing and is often the lowest value product generated, making profitability difficult. Additionally, numerous environmental concerns surround energywood harvesting, such as potential increased erosion, applicability and adequacy of conventional water quality best management practices (BMPs), increased area in road network features due to increased machine trafficking, and reduced quantities of residual woody debris. Energywood harvesting operations have been established in the lower Mid-Atlantic region of the U.S. for several decades, and research examining these operations provides insight into various aspects of the sustainability of the practice in this region and similar locations elsewhere. Therefore, this research provides a literature review on the practice of energywood harvesting, followed by four studies on energywood harvesting operations in the lower Mid-Atlantic region of the U.S. The first study evaluated the productivity and costs of two Appalachian Mountain and three Coastal Plain energywood harvests, providing stakeholders with a comparison of harvesting operations that can be used to make better-informed decisions regarding the efficient and economical harvest of energywood. The second study compared estimated erosion, operational feature areas, BMP implementation rates, ground cover characteristics, and downed woody debris quantities following 10 energywood and 10 conventional harvests in the Mountains of Virginia. The third study detailed a survey conducted among energywood business owners in Virginia designed to characterize harvesting operations and markets, assess business owner opinions related to the current and future state of the industry, and update/expand the results of a previous survey from 2014. The fourth study combined data from the second study with data from two other independent studies, comparing site impact metrics from energywood and conventional harvests across the Mountain, Piedmont, and Coastal Plain regions of Virginia. In the first study, cut and haul costs averaged $32.07/tonne and ranged from $26.19 to $38.28/tonne. Hauling consistently comprised the largest function cost at an average of $12.24/tonne. Harvesting system analysis also highlighted the importance of ensuring a balanced equipment mix to lower costs and ensure efficiency. In the second study, conventional harvests had higher estimated erosion contributions from skid trails (P = 0.089) and averaged more estimated erosion mass overall than energywood harvests, despite being significantly smaller in size (P = 0.054). There was significantly less area in heavy slash (P = 0.076) and lower estimated mass of residual downed woody debris (P = 0.001) on energywood sites than conventional sites (10.98 and 27.95 tons/acre, respectively). Site-wide BMP implementation scores (P = 0.041), as well as those for Streamside Management Zones (SMZs) (P = 0.024), and skidding (P = 0.063) were significantly higher on energywood sites than conventional sites. BMP implementation scores were significant predictors of estimated erosion rates (P < 0.001, R² = 59%), indicating that adequate levels of existing water quality BMPs are effective for erosion control on both conventional and energywood harvests. The third study indicated that energywood harvesting operations in Virginia were generally conventional single-crew roundwood operations utilizing their own residues for energywood. Production levels varied widely with energywood comprising an average 31% of total production. Material was comminuted utilizing large (650 median horsepower) older (13.2 years average) whole-tree chippers fed by a single loader. Coastal Plain operations were larger scale than Piedmont operations, though those in the Piedmont had been in business longer. Businesses had a median of $400,000 USD invested in energywood production equipment, which was double their median investment in the previous survey. Logging businesses that had produced energywood longer were significantly (P = 0.0391) more likely to report profitability. In addition, loggers reported deriving numerous non-market benefits from energywood production (e.g., improved aesthetics and cleaner sites, leading to increased landowner satisfaction), with most business owners planning to continue production in the future. The fourth study revealed that estimated erosion was higher in the Mountains due to steep slopes and operational challenges. BMP implementation varied by region and harvest type, with energywood sites having better implementation than conventional sites, and conventional Mountain sites having lower implementation than other regions. Sufficient woody debris remained for BMPs on both harvest types in all regions, with conventional Mountain sites retaining twice that of Coastal Plain sites. BMPs effectively reduced potential erosion on both site types; therefore, increased implementation could likely lower erosion potential in problematic areas. Collectively, this research provides a wholistic representation of energywood harvesting operations in the lower Mid-Atlantic region of the U.S., allowing stakeholders in the region and other similar locations to make informed decisions regarding its sustainable harvest.
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