Donald L. Hagan

The misalignment of species adaptations with current environmental conditions can cause ecosystems to lose resilience, accumulate resilience debt, and transition to another state. Such a state change is evident in eastern North American broadleaf forests where dominant tree species are shifting from oaks ( Quercus spp.) to mesophytic species such as maples ( Acer spp.). The replacement of oaks is widespread and threatens the ecosystem services these forests provide, generating interest in using forest management to halt or reverse this change. The national Fire and Fire Surrogate (FFS) study was a large‐scale study of forest management practices, and the Green River FFS site in western North Carolina (initiated in 2001) offers the opportunity to understand how management actions affect oak forest resilience. The Green River FFS site implemented three experimental treatments replicated across three spatial blocks: mechanical felling of saplings and ericaceous shrubs (Mech), prescribed fire (Fire), and a combination (Mech + Fire), which were compared to untreated controls (Control). Here, we used this long‐running experiment to evaluate oak forest resilience by examining changes in overstory basal area and forest composition among overstory trees, saplings, and seedlings. We found that basal area increased in the Control and Mech treatments, was unchanged in the Fire treatment, and decreased in the Mech + Fire treatment as a result of mortality. Oak sapling abundances increased with reduced basal area, a pattern not found with the major mesophytic representative, maples. This suggests that oaks are well positioned to recruit to the overstory where basal area has decreased due to overstory mortality, and at the Green River FFS site, this was best achieved in the Mech + Fire treatment. Creating conditions where oak saplings have an advantage over maples requires the mortality of some overstory trees, including desirable oaks. Taken together, our findings suggest that the misalignment of oak traits and current environmental conditions has led to resilience debt, which may be reduced when management actions mimic a severe disturbance that results in the opening of the canopy. Thus, management actions that combine mechanical felling and repeated prescribed fires may promote sustained oak dominance in the future.

Wood ducks (Aix sponsa) are common year‐round residents of wetlands throughout the southeastern United States. Evidence suggests >90% of the North American wood duck population nests in natural tree cavities rather than in artificial nest boxes. However, few studies have investigated the occurrence of these cavities, particularly across the wood duck's southern breeding range. We aimed to determine forest and tree characteristics associated with the presence of cavities suitable for wood duck nesting and model densities of potential nesting cavities within our study area. We established 20‐m‐radius plots (n = 166) across 5 dominant forest types in South Carolina, USA, and inspected 4,633 trees with diameter at breast height (DBH) > 22 cm for cavities. We identified 225 potential cavities, of which we deemed 69% were cavities and 14% were cavities suitable for nesting wood ducks. We found total cavity and suitable cavity densities at our study sites were greatest in oak (Quercus spp.), gum (Nyssa spp.), and cypress (Taxodium spp.) stands (x̄ = 19.35 ± 20.27 [SE] cavities/ha, n = 474,145 and x̄ = 4.20 ± 5.12 cavities/ha, n = 102,827, respectively). The best‐fit model for cavity presence had a positive effect for site index, DBH (cm), and stand age and a minor negative effect for tree density (km²). Results for suitable cavity presence also showed a positive effect for DBH and stand age (years), a negative effect for tree density, and no effect for basal area (m²). We used an optimized hot spot analysis using our findings to identify areas with >90% confidence of suitable cavity occurrence, which resulted in 861 ha of area with predicted suitable cavities (1.0% of the total sample area [89,559 ha]). Increasing our understanding of the relative abundance of cavities and cavities suitable for wood duck nesting and the identification of tree and stand metrics that influence the occurrence of cavities and those suitable to wood ducks promotes efficient management of forest and timber harvest practices beneficial to nesting wood ducks.

The national Fire and Fire Surrogate (FFS) study was initiated more than two decades ago with the goal of evaluating the ecological impacts of mechanical treatments and prescribed fire in different ecosystems across the United States. Since then, 4 of the original 12 sites remain active in managing and monitoring the original FFS study which provides a unique opportunity to look at the long‐term effects of these treatments in different regions. These sites include California (Blodgett Forest Research Station), Montana (Lubrecht Experimental Forest), North Carolina (Green River Game Land), and Ohio (Ohio Hills). Although regions differed in ecosystem type (e.g., conifer‐ vs. hardwood‐dominated), the overall goals of the FFS study were to promote desirable, fire‐adapted species, reduce fire hazard, and improve understory diversity. Our study uses multivariate techniques to compare how these desired outcomes were maintained over the last 20 years and discusses whether we would modify the original treatments given what we know now. Our findings indicate that mechanical treatments and prescribed fire can promote desired tree species, mitigate potential fire behavior by reducing fuels and retaining larger‐sized trees, decrease tree mortality, and stimulate regeneration—effects that are still apparent even after 20 years. However, we also found that maintaining desired outcomes was regionally specific with western sites (California and Montana) showing more desirable characteristics under mechanical treatments, while the eastern sites (North Carolina and Ohio) showed more desirable characteristics after prescribed burning. The beneficial effects of treatment were also more apparent in the long term when sites followed up with repeated treatments, which can be adapted to meet new objectives and conditions. These findings highlight the FFS study as an invaluable resource for research and provide evidence for meeting long‐term restoration goals if treatments can be adapted to ecosystem type, be maintained by repeated treatments, and accommodate new goals by adapting treatments to changing conditions.

The logging industry in the United States faces a demographic shift with aging owners and a decline in intergenerational business transfers. This pilot study explores the potential for new businesses led by minority groups, beginning loggers, and young entrepreneurs in the southeastern United States. Interviews with nine minority, beginning, and young (MBY) logging business owners and four forestry/logging associations uncovered challenges, including high startup costs, limited access to financing and funds, difficulty hiring skilled workers, low profit margins, and a lack of established professional networks. These MBY loggers are well educated and exhibit productive businesses, with an average investment of between $100,000 and $499,999. Proposed solutions to help more MBY logging business owners get started encompass government grants, low-interest loans, marketing initiatives, and legislative measures. Results are limited, and this study serves as a first glimpse into MBY logging business owners’ challenges; additional attention is needed for this population of logging business owners. Study Implications: Understanding the present status and challenges faced by minority, beginning, and young (MBY) logging business owners is instrumental for the industry, as the trend of intergenerational logging business transfer is declining. The study’s results suggest that support from the forest products industry and the government, such as government grants, low-interest loans, and strategic marketing, can enhance the sustainability of MBY logging businesses. These measures, coupled with legislative support, could help to address immediate challenges, such as high startup costs, and lay the groundwork for fostering a resilient logging industry.

This archive contains research data collected and/or funded by Forest Service Research and Development (FS R&D), U.S. Department of Agriculture. It is a resource for accessing both short and long-term FS R&D research data, which includes Experimental Forest and Range data. It is a way to both preserve and share the quality science of our researchers.

Global use of renewable energy has risen over the past few decades because of international energy policy changes, new legislation, and an effort to create a more sustainable energy source for a rapidly growing global population. One of these renewable energy sources is biofuels, specifically in the form of wood pellets created from wood chips. Wood pellet manufacturers in the southeastern United States must adhere to rigid quality-control standards of the European markets where their pellets are shipped and consumed. Thus, there is a need to improve our understanding of the factors that influence the quality of the source materials. Higher heating value (HHV), moisture content (MC), ash content, elemental composition, and size stratification are all important quality factors to consider when analyzing wood chips. Variations in these quality factors can cause longer drying times, blockages in feed systems, excess waste, and fluctuations in energy output. The objective of this study was to quantify these quality factors across multiple sources of wood chips. Softwood and hardwood in-woods chip samples as well as softwood mill residual chips were collected from thinnings and clear-cuts across the southeastern United States. Softwoods had a greater HHV and MC than hardwood chips, with 18,949 kJ/kg and 18,242 kJ/kg, respectively. Softwood thinnings had the highest HHV and lowest ash content. However, only 4 of the 60 samples analyzed were from softwood thinnings. This study provides an overview of the variation in wood chip quality across the southeastern United States.

Background: Fire seasonality is important for forest managers to consider when restoring historical disturbance regimes and recovering native ecosystem structure and composition, but it is less understood and less frequently studied than other aspects of fire ecology. In the Southern Appalachians, historical fires likely occurred most often in late spring and early summer when fuels were dry and canopy conditions were conducive to fire; however, most prescribed fires today occur during the dormant season (January–March). Because fire behavior can vary seasonally, it is important for forest managers to understand the practical applications of fire season in order to burn at a time that meets management objectives. Therefore, we investigated the effect of fire seasonality on forest structure and land cover diversity in the Southern Appalachians. Results: Using a complete randomized block design, we analyzed leaf-on canopy cover imagery with ArcGIS Pro to compare canopy cover and forest structure between growing and dormant season burns. We compared imagery between three blocks, each with an unburned control unit, dormant season burn, and growing season burn, and found an average of 8.84% (SE = ± 1.46) reduction in canopy cover in growing season treatment units from pre-burn (2017) to post-burn (2019) compared to 5.21% (SE = ± 1.51) reduction in dormant season treatment units and 0.01% (SE = ± 0.009) reduction in unburned controls. Canopy cover reductions corresponded with substantial increases in early- and mid-successional habitat, edge length, and land cover diversity — especially in growing season burn treatment units. Conclusions: Our results indicate that early growing season burns are more effective than dormant season burns at enhancing forest structural heterogeneity. Early growing season burns, therefore, may be a viable option for forest managers looking to expand their burn season and achieve restoration and management goals faster than traditional dormant season burns.

Timber harvesting operations are increasingly used to restore sensitive habitats such as longleaf pine (Pinus palustris Mill.) ecosystems. However, logging companies are often functionally limited by operational costs and site-specific productivity potential. By employing a time study, this project quantified the cost and productivity of a two-person logging crew using conventional equipment in a South Carolina southern pine timber harvest used to restore a longleaf pine savanna ecosystem. Our study found that the feller-buncher, grapple skidder, and knuckle-boom loader produced, on average, 60.7, 23.6, and 45.2 tonnes per Productive Machine Hour (PMH), respectively. When the knuckle-boom loader was exclusively loading log trucks, productivity increased to 48.4 tonnes per PMH. Additionally, a machine rate analysis found that the total cost for each machine was 108.83 USD, 122.92 USD, and 121.25 USD per PMH, respectively, with a total per tonne cost of cutting, skidding, and loading amounting to 9.68 USD. Our findings indicate that restoration harvesting conducted in this manner under similar environmental conditions and price points may remain profitable for both landowners and logging companies. Moreover, the limitations of operating with a two-person crew resulted in minimal negative effects for both profitability and productivity, making it a viable option for similar restoration operations.