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Research Highlights: Seasonal variation in environmental conditions coinciding with reproductive and energetic demands might result in seasonal differences in species-specific habitat use. We studied a winter assemblage of insectivorous bats and found that species acted as habitat generalists during winter compared to expectations based on the summer active season. Background and Objectives: In temperate regions, seasonal fluctuations in resource availability might restructure local bat assemblages. Initially perceived to only hibernate or migrate to avoid adverse winter conditions, temperate insectivorous bats appear to also employ intermediate overwintering strategies, as a growing body of literature suggests that winter activity is quite prevalent and even common in some lower latitude areas. However, to date, most studies have exclusively assessed habitat associations during summer. Because habitat use during summer is strongly influenced by reproduction, we hypothesized that habitat associations might differ during the non-reproductive winter period. We used acoustic monitoring to assess the habitat associations of bats across a managed pine landscape in the southeastern United States. Materials and Methods: During the winters of 2018 and 2019, we deployed acoustic detectors at 72 unique locations to monitor bat activity and characterized vegetation conditions at two scales (microhabitat and landscape). We used linear mixed models to characterize species-specific activity patterns associated with different vegetation conditions. Results: We found little evidence of different activity patterns during winter. The activity of three species (hoary bat: Lasiurus cinereus; southeastern myotis: Myotis austroriparius; and tricolored bat: Perimyotis subflavus) was not related to vegetation variables and only modest relationships were evident for four other species/groups (big brown bat: Eptesicus fuscus; eastern red bat: L. borealis; Seminole bat: L. seminolus; evening bat: Nycticeius humeralis; and Brazilian free-tailed bat: Tadarida brasiliensis). Conclusions: During winter, the bats in our study were active across the landscape in various cover types, suggesting that they do not exhibit the same habitat associations as in summer. Therefore, seasonal differences in distributions and habitat associations of bat populations need to be considered so that effective management strategies can be devised that help conserve bats year round. [ABSTRACT FROM AUTHOR]

Longleaf pine (Pinus palustris) savanna characterized by open‐canopy, diverse herbaceous vegetation, and high amounts of bare soil once covered much of the southeastern United States Coastal Plain. The unique structural and vegetative conditions of this ecosystem support endemic reptiles and amphibians that have declined as longleaf pine forests have been lost or degraded. Private working pine (Pinus spp.) forests managed for timber production now occur throughout the southeastern United States and have replaced much of the historical longleaf pine savanna. The examination of herpetofaunal (reptile, amphibian) communities in private working loblolly pine (P. taeda) landscapes, particularly in the western Gulf Coastal Plain is lacking. Using repeated field surveys and hierarchical community occupancy models, we examined occupancy and species richness of herpetofauna across 81 sites spanning gradients of management practices, vegetative conditions, and soil composition in northwestern Louisiana, USA, 2017–2019. Young pine stands (<6 yr) exhibited structural characteristics most similar to mature longleaf pine reference sites (>30 yr), while mid‐aged stands (13–26 yr) often featured closed canopy and dense midstory. Vegetation conditions varied widely depending on landscape characteristics and site‐specific disturbance regimes. We documented 43 species of herpetofauna, including 9 open‐pine‐associated species. Occupancy of open‐pine‐associated herpetofauna was positively associated with open‐canopy and understory conditions, and sandy soil area. Sites providing open‐canopy conditions were often occupied by open‐pine‐associated species regardless of overstory type and disturbance method. Overall richness of herpetofauna was greatest at sites with moderate canopy cover outside of sandy soil regions. Working pine landscapes in the western Gulf Coastal Plain can support diverse herpetofaunal assemblages, including open‐pine‐associated species, when management practices maintain open‐canopy conditions on sandy, upland soils. More broadly, our results provide insight into how forest management practices affect herpetofauna and may guide practices that can contribute to conservation value of working pine forests. [ABSTRACT FROM AUTHOR]

The seasonal habitat selection by female wild turkeys on a well managed pine landscape in Mississipi indicates that the well managed pine landscape provides a favorable habitat for wild turkey during most of the time in the year.

Highlights • Thinned pine stands have structural conditions consistent with open pine woodlands. • Prescribed fire and herbicide applied after thinning can extend open pine condition. • Duration of open pine condition is influenced by site index and planting density. • Connectivity of open pine patches can facilitate movement for many open pine species. • Gopher tortoises have an even flow of habitat in regenerating and thinned stands. Abstract Pine forests managed for economic return comprise 19% of southeastern U. S. forests and can provide vegetation structure and composition necessary for many wildlife species adapted to open pine conditions. However, in the absence of frequent fire and other disturbance in southeastern pine (Pinus spp.) forests, midstory hardwoods create closed canopy conditions limiting value of pine stands for many endemic, disturbance-adapted wildlife species. Limitations of past research investigating exact mechanisms for producing and maintaining open pine conditions in managed pine systems have led to a paucity of information regarding ecoregion applications and outcomes. This study evaluated (1) to what extent managed pine stands replicate open pine structural conditions and (2) to what extent managed pine stands provide habitat for the gopher tortoise, an open pine keystone species. We used summary statistics from existing literature to identify structural metrics provided by managed loblolly pine (P. taeda) stands and compared them to disturbance-maintained open pine woodlands. We used spatially-explicit forest management simulations to determine amount and configuration of open pine woodland conditions within two large (>9000 ha), economically-feasible managed pine landscapes in the East and West Gulf Coastal Plains ecoregions. As a case study, we estimated availability and connectivity of gopher tortoise (Gopherus polyphemus) habitat, in managed pine stands of the East Gulf Coastal Plains. Pine stands planted at ≤1310 stems/ha (≤530 stems/ac) provide up to four years of "excellent" open pine condition for wildlife following commercial thinning, based on desired conditions for southern pine forests, with temporal availability depending on site quality. Mid-rotation applications of prescribed fire and selective herbicide can extend "excellent" open pine condition initiated by commercial thinning up to an additional four years. Landscape metrics indicated that, under typical management practices, open pine stands can be spatially and temporally connected to the extent necessary to facilitate among-patch movement for many open pine-adapted species of conservation concern. Our landscape analyses indicated tortoises using primarily regenerating and thinned stands potentially can have a relatively even flow of suitable habitat conditions and opportunities to move to adjacent or nearby open stands when currently-occupied stands reach canopy closure. The disturbance regimes inherent in pine plantation management create diverse landscapes that conserve plant and wildlife biodiversity while meeting economic objectives. Therefore, pine plantations may complement current conservation efforts for open pine woodland species dependent on or tolerant of large-scale disturbance and shifting habitat conditions while offering refuge for high vagility species. [ABSTRACT FROM AUTHOR]

Abstract: Switchgrass (Panicum virgatum) intercropping is a novel forest management practice for biomass production intended to generate cellulosic feedstocks within intensively managed loblolly pine‐dominated landscapes. These pine plantations are important for early‐successional bird species, as short rotation times continually maintain early‐successional habitat. We tested the efficacy of using community models compared to individual surrogate species models in understanding influences on nest survival. We analysed nest data to test for differences in habitat use for 14 bird species in plots managed for switchgrass intercropping and controls within loblolly pine (Pinus taeda) plantations in Mississippi, USA. We adapted hierarchical models using hyper‐parameters to incorporate information from both common and rare species to understand community‐level nest survival. This approach incorporates rare species that are often discarded due to low sample sizes, but can inform community‐level demographic parameter estimates. We illustrate use of this approach in generating both species‐level and community‐wide estimates of daily survival rates for songbird nests. We were able to include rare species with low sample size (minimum n = 5) to inform a hyper‐prior, allowing us to estimate effects of covariates on daily survival at the community level, then compare this with a single‐species approach using surrogate species. Using single‐species models, we were unable to generate estimates below a sample size of 21 nests per species. Community model species‐level survival and parameter estimates were similar to those generated by five single‐species models, with improved precision in community model parameters. Covariates of nest placement indicated that switchgrass at the nest site (<4 m) reduced daily nest survival, although intercropping at the forest stand level increased daily nest survival. Synthesis and applications. Community models represent a viable method for estimating community nest survival rates and effects of covariates while incorporating limited data for rarely detected species. Intercropping switchgrass in loblolly pine plantations slightly increased daily nest survival at the research plot scale (0.1 km2), although at a local scale (50 m2) switchgrass negatively influenced nest survival. A likely explanation is intercropping shifted community composition, favouring species with greater disturbance tolerance. [ABSTRACT FROM AUTHOR]

Fire-maintained pine ( Pinus spp.) forests, characterized by a diverse herbaceous layer, sparse midstory layer, and a dominant pine overstory, once covered approximately 30 million ha in the southeastern United States. Fire suppression, landscape changes, and land management changes have contributed to reduced suitability of many pine stands for fire-dependent species, including many avian species in regional decline. However, intensively managed loblolly pine ( P. taeda ) stands treated with prescribed fire and herbicide could help restore or maintain fire-dependent communities within working landscapes. Therefore, we investigated avian responses to combinations of prescribed fire and herbicide (imazapyr) treatments within a matrix of intensively managed pine stands in east-central Mississippi, USA. We used a randomized complete block design of 6 mid-rotation, thinned pine stands (blocks) each with 4 treatments (control, burn only, herbicide only, burn + herbicide) assigned to 10-ha experimental units. We applied imazapyr herbicide (Arsenal®) during fall 1999 and burned units during winter every 3 years, beginning in 2000. We conducted avian point counts from year pre-treatment (1999) through 9 years post-treatment (2000–2008) and summarized annual vegetation structure and composition. We used 34 of 64 observed avian species for analyses using mixed models, repeated measures ANCOVA. Across the 9-year post-treatment study period, fire and imazapyr differentially affected avian communities with our combination treatment (fire + imazapyr) favoring high-priority, open pine bird species most. However, remaining treatments (burn only, imazapyr only, controls) provided additional vegetation gradients for species preferring greater structure diversity or canopy coverage. Our results indicated that fire and herbicide treatments can maintain vegetation structure attractive to a bird community of high-conservation value, while concurrently meeting economic and sustainable forestry goals. Although primarily managed for economic gain, intensively managed forests can provide suitable habitat conditions for avian species of conservation concern helping land managers meet biodiversity objectives. [ABSTRACT FROM AUTHOR]

Understanding how changes to habitat characteristics affect behaviors is necessary to integrate biodiversity goals with land management. Managed forests are a significant landscape component in the southern United States and provide opportunities for conservation alongside production of wood products. We investigated behavioral responses of rodents to differences in understory habitat characteristics from intercropping switchgrass ( Panicum virgatum ), a native biofuel feedstock, in intensively managed loblolly pine ( Pinus taeda ) stands. Previous research indicated that planting switchgrass increased rodent population abundance but reduced recruitment and community diversity. To understand potential mechanisms underlying our previous results, we measured behaviors of individual cotton rats ( Sigmodon hispidus ), a grassland specialist, to planted switchgrass. We hypothesized that female territory size, foraging activity, overlap with other adult females, and reproduction indices would differ among treatments (switchgrass monocrop, intercropped switchgrass, and control plots) due to variation in grass abundance and vertical vegetation cover. We conducted live-trapping, radio telemetry, and foraging activity surveys on cotton rats during summers of 2013–2015. We found no treatment effect on territory size, but foraging activity was 2 times higher in monocrop than control plots. We also found a positive relationship between female spatial overlap and percentage of grass in control plots and evidence for higher reproductive indices in control than monocrop plots. Our results suggest that cotton rats in monocrop plots exhibited unexpected behaviors, and monocrop plots may serve as population sinks with low rodent diversity. Overall, results from this replicated experiment suggested that intercropping provides adequate food and cover to maintain rodent populations and produce forest products. [ABSTRACT FROM AUTHOR]

ABSTRACT Switchgrass ( Panicum virgatum) is a cellulosic feedstock for alternative energy production that can be grown between rows of planted pines ( Pinus spp.) within intensively managed forests. Southeastern planted pine occupies 15.8 million ha and thus, switchgrass intercropping could have far-ranging effects on plant communities and biomass production within these forests if broadly implemented. Such intercropping could lead to alterations to plant communities that may cause bottom-up ecological changes affecting ecologically, economically, and socially important wildlife, such as white-tailed deer ( Odocoileus virginianus; deer). Therefore, we tested whether intercropping switchgrass in loblolly pine ( P. taeda) plantations would cause switchgrass to dominate vegetative biomass thereby decreasing biomass of forages and reducing white-tailed deer nutritional carrying capacity (NCC), or whether disturbance associated with establishment and harvest of switchgrass would facilitate ruderal forbs, and thereby increase biomass of preferred deer forages and increase NCC. In a randomized complete block design, we assigned 2 treatments (intercropped switchgrass and a standard pine management control) to 4 replicates of 10-ha experimental units in Kemper County, Mississippi during summers of 2011−2015. We detected 323 plant species. Intercropping switchgrass had little effect on plant biomass production, and did not affect white-tailed deer NCC at a maintenance diet of 6% crude protein. Intercropping provided additional disturbance allowing high-protein content ruderal plants to colonize, and temporarily increased (3 yr) deer NCC at the 14% crude protein diet considered necessary to support lactation. However, concomitant with a sharp increase in switchgrass biomass in the third year of the study, NCC dropped to levels similar to traditionally managed pine stands. Switchgrass intercropping is not a reliable means of increasing deer NCC as a management strategy but does not appear to reduce carrying capacity in the short-term relative to standard intensive pine management. © 2017 The Wildlife Society. [ABSTRACT FROM AUTHOR]

In the United States, intensively managed forests (IMFs) comprise approximately 9% (27.9 million ha) of total forest area. These forests are primarily in highly productive areas and are managed primarily for wood and fiber production. Intensively managed forests provide both opportunities and constraints for conservation of vertebrate biodiversity. A comprehensive review of these opportunities and limitations within the U.S. is lacking, so we reviewed effects of typical silvicultural management regimes within IMFs on terrestrial vertebrate species. The typical silvicultural regime in IMFs includes practices associated with establishing forest management units (stands), weed control, intermediate thinning, and final harvest. Effects of intensive forest management on vertebrate diversity are mostly indirect through habitat modification. Terrestrial vertebrate responses to intensive forest management are species-specific and directly linked to intensity and extent of habitat modification. Shorter crop tree rotations compress successional stages and limit development and recruitment of mature forest structures (e.g., snags, den/roost trees, coarse woody debris). During stand establishment, increased intensification of site preparation and weed control tends to result in lower vertebrate diversity. Generally, vertebrate diversity of intensively managed stands is progressively reduced after stand establishment as canopy closure occurs and sunlight to the forest floor is restricted, reducing vegetation structural complexity. However, intermediate management practices like thinning, which re-opens the forest canopy, generally have positive or neutral effects on most vertebrate taxa. Final tree harvest removes the overstory and, predictably, vertebrate taxa depending on older or undisturbed forest conditions decline and early seral species increase. To ameliorate negative effects of final harvest on terrestrial vertebrate diversity, land managers have instituted various practices, including retaining habitat elements, protecting riparian zones and sensitive ecological areas, and limiting final harvest unit size as well as how soon an adjacent forest patch can be harvested. Juxtaposition and interspersion of forest stands of varying ages are important determinants of terrestrial vertebrate responses to intensively managed landscapes. A typical intensively managed landscape contains a variety of stand ages, forest types, and other features (e.g., streams, mature forest stands, set-aside areas) that provide habitat for a diversity of terrestrial vertebrate species. Landscape context has direct ramifications for terrestrial vertebrate diversity in intensively managed landscapes, with negative effects more pronounced in forests imbedded in agriculture or anthropogenic landscapes. Most field studies have been of short duration (<5 years) and localized (e.g., multiple stands in an area), hence we call for a greater commitment to longer-term research and monitoring replicated across landscapes. Significant research gaps include how to improve functionality of retained structures, riparian zones, and unique ecological communities, whether vertebrates are evolving or adapting to the rapid changes in habitat conditions characteristic of IMFs, and how landscape context, including spatial distribution of varying stand ages, affects vital rates of terrestrial vertebrate species (hereafter wildlife). [ABSTRACT FROM AUTHOR]

Intensively-managed pine (Pinus spp.) have been shown to support diverse vertebrate communities, but their ability to support invertebrate communities, such as wild bees, has not been well-studied. Recently, researchers have examined intercropping switchgrass (Panicum virgatum), a native perennial, within intensively managed loblolly pine (P. taeda) plantations as a potential source for cellulosic biofuels. To better understand potential effects of intercropping on bee communities, we investigated visitation of bees within three replicates of four treatments of loblolly pine in Mississippi, U.S.A.: 3-4 year old pine plantations and 9-10 year old pine plantations with and without intercropped switchgrass. We used colored pan traps to capture bees during the growing seasons of 2013 and 2014. We captured 2507 bees comprised of 18 different genera during the two-year study, with Lasioglossum and Ceratina being the most common genera captured. Overall, bee abundances were dependent on plantation age and not presence of intercropping. Our data suggests that switchgrass does not negatively impact or promote bee communities within intensively-managed loblolly pine plantations. [ABSTRACT FROM AUTHOR]

Open canopy conditions in southeastern pine ( Pinus spp.) forests were historically maintained by frequent fire and other disturbances, without which midstory hardwoods create closed canopy conditions limiting value of pine stands for many endemic, disturbance-adapted species. Intensively managed pine forests, which comprise 19% of forests in the southeastern U.S., can emulate historical open pine conditions, providing appropriate vegetation structure and composition for many endemic species. However, exact mechanisms for producing and maintaining open pine conditions and subsequent effects on biodiversity have not been examined across regions and stand ages. To better inform managers about options for providing open pine conditions in intensively managed pine stands, we used meta-analyses to examine biodiversity and open pine focal species responses to 5 stand establishment intensities and 4 mid-rotation practices (prescribed fire, selective herbicide, fire and herbicide combination, and thinning). We calculated 1742 biodiversity and 169 open pine focal species effect sizes from 42 publications of manipulative studies at 14 unique study sites in managed loblolly pine ( P. taeda L.) forests in the Atlantic and Gulf Coastal Plains of the southeastern U.S. We quantified diversity and abundance responses by taxa and management practices for vegetation, birds, amphibians, reptiles, small mammals, and invertebrates. Diversity and abundance responses generally decreased as stand establishment intensity increased, but those reductions appeared to be short-term (<3 years). Birds and open pine focal species responded positively to chemical stand establishment relative to a mechanically-prepared control. Thinning elicited positive diversity and abundance responses from reptiles and small mammals. Effects of prescribed fire, selective herbicide, and their combination on biodiversity responses varied by taxa (e.g., following fire, vegetative and avian diversity increased but amphibian and invertebrate diversity decreased). Further research is warranted on under-represented taxa (e.g., herpetofauna and invertebrates) in literature and long-term effects of forest management on biodiversity. Understanding how silvicultural management practices produce and maintain open pine forest conditions and influence biodiversity responses is necessary to inform opportunities for open-pine wildlife communities in working forested landscapes. [ABSTRACT FROM AUTHOR]

The ability to fully evaluate potential relationships between forest management and bats is limited without information from relevant spatial scales. Further, knowledge of bat ecology in intensively managed forests is fairly limited even though these forests are a substantial portion of the forested landscape in the southeastern U.S. Therefore, we used occupancy models to examine influence of small-scale vegetation characteristics and large-scale spatial features on foraging patterns of bats within 6 managed-pine ( Pinus spp.) forest landscapes in the southeastern U.S. Coastal Plain. We conducted repeated acoustic surveys to determine species presence/non-detection and evaluated a priori models relating detection probability and occupancy to site- and landscape-level metrics for 6 species/genera. Detection of big brown ( Eptesicus fuscus ) and eastern red ( Lasiurus borealis )/Seminole ( L. seminolus ) bats (eastern red and Seminole bats combined) decreased with increasing basal area, and detection of big brown and Brazilian free-tailed bats ( Tadarida brasiliensis ) increased over the summer sampling period. Relationships between occupancy and habitat metrics were species-specific but consistent with previous studies. Occupancy for most bat species was lower at sampling sites with higher vegetation clutter and higher basal area. In contrast to most previous studies, occupancy of all bat species investigated was unrelated to or negatively influenced by distance to water. Although site- and landscape-level features influenced occupancy, our results indicate that site-specific features (vegetation clutter and basal area) influenced most species. Therefore, stand-level management activities that decrease vegetation structure, such as thinning intermediate-aged stands and/or controlling midstory vegetation (e.g., fire or herbicide applications), likely will maintain or increase suitability of managed pine forest stands and landscapes for many bat species in the southeastern Coastal Plain. The forest mosaics that we sampled, consisting primarily of managed pine stands intermingled with non-production habitat types, supported a large proportion of the bat community associated with forests of the Coastal Plain which suggests the compatibility of timber production and bat conservation objectives. [ABSTRACT FROM AUTHOR]

Intensively managed pine forests in the southeastern U.S. now cover approximately 15.8 million ha. Forest managers are increasingly expected to consider biodiversity in land management decisions. Habitat management, particularly dormant-season prescribed fire with or without prior herbicide application may provide an opportunity for achieving sustainability goals relative to biodiversity in intensively managed pine stands. Therefore, we investigated vegetation structure, coverage, and diversity responses to combinations of prescribed fire and herbicide (imazapyr) treatments within mid-rotation, thinned, intensively managed pine stands within a managed forest matrix in east-central Mississippi, USA during 1999-2008. We used a randomized complete block design of 6 mid-rotation, thinned pine stands (blocks) each with 4 treatments [control, burn only (dormant-season 3 year fire return interval), herbicide only (Arsenal AC® at 12 oz./acre), burn + herbicide) assigned to 10-ha experimental units. We measured vegetation structure (understory, midstory, and overstory components) and understory plant coverage using standard techniques from one year pre-treatment (1999; our baseline) through 9 years post-treatment (2008). To evaluate treatment effects, we used repeated measures mixed models analysis of covariance with baseline data as our covariate. We detected 338 plant species including 140 forbs, 5 ferns, 35 grasses, 11 herbaceous vines, 21 legumes, 26 sedges and rushes, 9 semi-woody vines, 76 woody plants, and 15 woody vine species. Treatment effects included concomitant reductions in upper level visual obstruction (m), increased herbaceous understory coverage, and hardwood midstory competition reduction. Herbicide was more effective at reducing hardwood midstory basal area, but repeated disturbances by prescribed fire maintained favorable vegetation structure conditions and improved understory plant species diversity throughout the latter years of study. Overstory pine basal area demonstrated positive responses to treatments. Prescribed fire and herbicide, within thinned, intensively managed pine stands at levels investigated here, appears to promote a stand structure consisting of a pine overstory and a diverse understory, reflective of historic conditions in the southeastern U.S. Implementation of these treatments can help forest managers achieve sustainable forestry goals in intensively managed pine stands of the southeastern U.S. [ABSTRACT FROM AUTHOR]

Abstract: Intensively managed pine occupies 22% of the forest land base in the southeastern United States. More fully understanding effects of standard silvicultural practices on biodiversity could improve wildlife management recommendations on intensively managed landscapes. Although multiple stand-establishment techniques (i.e., site preparation and chemical herbaceous control of competition) are used for forest regeneration, we lack an understanding of causal mechanisms for bird community responses during stand establishment through canopy closure. Therefore, we investigated bird community responses to five stand-establishment treatments in intensively managed pine (Pinus spp.) stands in the Lower Coastal Plain of Mississippi, USA as a function of changes in vegetation structure and coverage. We used a randomized complete block design of four pine stands (blocks) divided into five experimental units and with treatments randomly assigned to each unit. Our treatments represented available establishment practices and increased in intensity from mechanical or chemical site preparation with subsequent banded herbaceous control to mechanical and chemical site preparation with 2years of subsequent broadcast herbaceous weed control applications. We sampled bird communities with point counts and measured visual obstruction, pine tree height, woody stem density, and vegetation structure and coverage by growth form (e.g., forb, fern, grass, legume, pine, sedge and rush, woody non-pine, vine). Bird communities had an overall negative response to increasing intensity of stand-establishment treatments, and temporal trends from site preparation to canopy closure were absent. Common species appeared relatively unaffected by treatments. However, presence of species with high conservation value and availability of early successional habitat conditions emphasized conservation potential of intensively managed pine forests for birds and justify further experimental investigation of bird community responses to stand-establishment treatments. We recommend forest managers continue to incorporate a variety of stand establishment practices to ensure habitat availability for a variety of bird species, and that researchers further investigate mechanistic factors of avian community responses to silvicultural practices. [Copyright &y& Elsevier]

Abstract: Prescribed fire and herbicide are silvicultural tools that influence biodiversity in intensively managed, mid-rotation pine (Pinus spp.) stands. These forest types are common in the southeastern United States and are economically and ecologically important. Understanding biodiversity responses to silvicultural treatments is important to fully understand management approaches to maintain sustainability of forestry practices. Information is incomplete regarding response of carabid beetles (Coleoptera: Carabidae) to management, and they can serve as indicator species for habitat change caused by disturbance. Therefore, we investigated direct effects of independent and combined applications of repeated, dormant season prescribed burns on a 3-year fire return interval and a one-time application of imazapyr herbicide (Arsenal®) on forest floor carabid assemblages in intensively managed, mid-rotation loblolly pine (Pinus taeda) stands of east-central Mississippi, USA. We captured 1900 individuals dominated by 7 species using pitfall traps from May–October 2004–2007 in a randomized complete block experimental design. Negative responses to treatments by carabid species (i.e., less abundance) were most common, but differential treatment effects by fire with or without imazapyr indicated potential for long-term conservation via increased habitat heterogeneity if mid-rotation treatments are applied across the landscape. [Copyright &y& Elsevier]

Intensive forestry presents opportunities for intercropping herbaceous biomass species between crop tree rows for producing cellulosic feedstocks. Switchgrass (Panicum virgatum) and other native prairie grasses are being evaluated as potential biofuel crops. It is unclear how intercropping within intensively managed forests will affect biodiversity compared with similar forests under traditional timber management. However, research with grasses in row crop agriculture suggests some basic principles. Effects will likely vary with habitat needs of individual species and communities. Additionally, intercropping regimes favoring mixed native warm-season grasses over switchgrass only, spring harvests over fall, and rotational harvests producing mosaics of grass heights would likely benefit biodiversity. A critical knowledge gap is how potential edge effects of growing crop trees may influence habitat quality of intercropped stands. Although biomass intercropping may increase diversity by adding predominantly grass components to intensively managed forest landscapes, predictions about biodiversity response are not possible until more research is done. [ABSTRACT FROM AUTHOR]

Abstract: Although intensively managed pine forests are common in the southeastern US, few studies describe how combinations of mechanical (MSP) and chemical site preparation (CSP) and herbaceous weed control (HWC) techniques affect bird communities that use early successional habitats within young pine forests. Therefore, we examined effects of six treatments of increasing management intensity via combinations of MSP (strip-shear and wide spacing or roller chop and narrow spacing) and CSP (application or no application) treatments with banded or broadcast HWC on bird communities in six loblolly pine (Pinus taeda) plantations in the Coastal Plain of North Carolina, USA, for 8years following site preparation. Wide pine spacing and strip-shear MSP increased bird abundance and species richness over narrow spacing and chopped MSP for 6years after planting. Chemical SP reduced bird abundance in year 2, increased bird abundance in year 6, had no effect on abundance after year 7, and did not affect species richness in any year. Total bird abundance and species richness were similar between banded and broadcast HWC. Site preparation and HWC had no effect on bird diversity and bird communities were most similar in treatments of similar intensity. Site preparation and HWC had few or no effects on birds based upon migratory status, habitat association, or conservation value. The addition of chemical site preparation or HWC had little effect on birds beyond pine spacing, and bird abundance was not proportional to management intensity. Although we observed treatment effects, all treatments provided habitat used by a variety of bird species, and pine plantations may play an increasingly important role in bird conservation as forests become fragmented and converted to other land uses and as natural processes that create early successional habitat, such as fire, are suppressed. [Copyright &y& Elsevier]

Abstract: Intensively managed loblolly pine (Pinus taeda) forests are common in the southeastern United States and offer opportunities for conservation of biologic diversity. Within intensively managed landscapes, stand establishment relies on combinations of mechanical and chemical site preparation and herbaceous weed control (HWC) to manage competing vegetation and increase pine production. However, few long-term studies have described relationships between intensity of stand establishment and effects on plant communities. Therefore, we examined effects of 6 treatments that varied in intensity via combinations of mechanical (wide spacing and strip shear or narrow spacing and roller chop) and chemical (application or no application) site preparation treatments with HWC (broadcast or banded) from 1 to 8years after site preparation on plant communities in loblolly pine plantations (n =6) in the Coastal Plain of North Carolina, USA. All treatments resulted in abundant and diverse plant communities. Chemical site preparation had short lived (⩽4year) effects on the herbaceous community but long-term effects on woody plants and pine cover. Increasing management intensity by including broadcast HWC or roller chop/narrow spacing did not additively reduce woody vegetation cover or species richness. However, broadcast HWC reduced grass, vine, and forb cover in the first year post-treatment. Average Morista community similarity values ranged from 0.69 to 0.89 among treatments and plots receiving the same chemical site preparation contained the most similar plant communities. Banded HWC can be paired with wide spacing to maximize herbaceous plant growth important for many wildlife species, particularly in the first few years after site preparation. Site preparation techniques should be tailored to local site conditions, plant communities, and management objectives. [Copyright &y& Elsevier]

Abstract: Demand for alternative energy sources has led to increased interest in intensive biomass production. When applied across a broad spatial extent, intensive biomass production in forests, which support a large proportion of biodiversity, may alter species composition, nutrient cycling and subsequently biodiversity. Because forest thinning and fuels treatment thinning are viewed as possible wide-spread biomass harvest options, it is important to understand what is known about forest biodiversity response to these practices and what additional information is needed by forest managers and policymakers. Therefore, we summarized documented relationships between forest thinning treatments and forest biodiversity from 505 biodiversity effect sizes (incl. taxa and guild abundance and species richness measures) from 33 studies conducted across North America. We used meta-analysis to summarize biodiversity response by region, taxa and harvest treatments. Biodiversity responses included species richness, diversity, abundance of taxa or groups of species (guilds) and abundance of individual species for birds, mammals, reptiles, amphibians, and invertebrates. Forest thinning treatments had generally positive or neutral effects on diversity and abundance across all taxa, although thinning intensity and the type of thinning conducted may at least partially drive the magnitude of response. Our review highlights the need for more research to determine effects of thinning on amphibians and reptiles and manipulative experiments designed to test the effects of biomass removal on biodiversity. [ABSTRACT FROM AUTHOR]

Abstract: Vegetation management, using prescribed fire and herbicides, is used in forestry applications to reduce competition with desired species, improve wildlife habitat, and meet other silvicultural objectives. Although plant communities resulting from such treatments are generally known, it is unclear how pre-treatment plant community structure may influence specific plant community responses. Therefore, to examine how species dominance may impact response of plant communities to vegetation management, we compared the top contributors to plant biomass (kgha−1) among prescribed fire and herbicide (imazapyr) treatments within intensively managed pine stands in east-central Mississippi, USA. Ninety-two species of 390 collected comprised 95% of plant biomass and six species comprised 55% of total biomass. Dominant species may have restricted plant diversity. Prescribed fire with and without imazapyr improved species richness but did not control some highly competitive species. None of the treatments tested is necessarily an optimal solution to control well-established understory plant species. Although management prescriptions consider exotic and invasive plant species, control of well-established native species should also be considered to tailor vegetation management to meet forestry and wildlife habitat objectives. More research is needed concerning plant response to multiple herbicide tank mixtures with and without prescribed fire to optimize future vegetation management for multiple objectives. [Copyright &y& Elsevier]

Herbicides, commonly used for vegetation management in intensively managed pine (Pinus spp.) forests of the southeastern United States, with and without fire, may alter availability of quality forage for white-tailed deer (Odocoileus virginianus; deer), an economically and socially important game species in North America. Because greater forage quality yields greater deer growth and productivity and intensively managed pine forests are common in the southeastern United States, forest managers would benefit from an understanding of fire and herbicide effects on forage availability to improve habitat conditions for deer. Therefore, we evaluated independent and combined effects of fire and herbicide (i.e., imazapyr) on forage biomass and deer nutritional carrying capacity (CC) on land owned and managed by Weyerhaeuser NR Company in east-central Mississippi, USA. We used a randomized complete block design of 6 pine plantations (blocks) divided into 4 10-ha treatment plots to each of which we randomly assigned a treatment (burn-only, herbicide-only, burn + herbicide, and control). We estimated biomass (kg/ha) of moderate- and high-use deer forage plants during July of 1999-2008, then estimated CC for diets to support either body maintenance (6% crude protein) or lactation (14% crude protein) with a nutritional constraints model. Herbaceous forages responded positively to fire and herbicide application. In most years, CC estimates for maintenance and lactation were greater in burn + herbicide than in controls. Maintenance-level CC was always greater in burn + herbicide than in controls, except at 1 year posttreatment. Burn + herbicide was 2.6-8.3 times greater (x¯ = 4.0) than control for lactation-level CC in 8 of 9 years posttreatment. We recommend fire and selective herbicides to increase high-quality deer forage in mid-rotation, intensively managed pine plantations. [ABSTRACT FROM AUTHOR]

Intensive pine (Pinus spp.) management is a primary land use in the southeastern United States. In eastern North Carolina, intensively managed pine stands often occur on land previously ditched and drained. Because modification of natural vegetation and water sources are known to affect dipteran community structure, we studied effects of intensive pine management on abundance and diversity of dipteran families in the northern coastal plain of North Carolina during 2006 and 2007. We used malaise traps and emergence traps to sample different types of forest stands (n = 143 sample nights) and water sources (n = 147 sample nights) in a managed pine forest and a natural forested wetland. Cecidomyiids were more abundant in stands with canopy cover, chironomids were more abundant at edges between forested stands and open canopy stands, and chloropids were more abundant in open canopy stands. Families Ceratopogonidae, Dolichopodidae, Ephydridae, Muscidae, Psychodidae, and Tipulidae were more abundant in the natural forested wetland than in all types of modified water sources. Dipteran diversity and evenness were highest in stands with open canopy and at forest edges, and highest in the natural forested wetland. Unmanaged, natural stands on the intensively managed landscape did not support a higher abundance or diversity of dipteran families than intensively managed stands. Restoration of natural wetlands may increase dipteran diversity in unmanaged stands. Heliponds, a modified water source, supported a comparable dipteran abundance to that of the natural forested wetland. Increased numbers of heliponds may facilitate higher dipteran abundance in managed pine landscapes. [ABSTRACT FROM AUTHOR]

The southern United Stales has significant area in managed pine (Pinus spp.) stands that contribute to terrestrial biodiversity via maintenance of forested areas, varied silvicultural practices resulting in diverse plant communities, stands in multiple successional stages interspersed with mature natural forests, and reduction of pressure on natural forests for wood products. However, conservation value of managed forests is dependent on factors such as product target, landscape context, management intensity, rotation length, stocking density, and ownership philosophy. Potential limitations include loss of natural forests, reduction in dead wood, constraints on stand structure, age and size of plantation trees, and economic pressure to increase management intensity. We recommend that landowners develop plans, including metrics for gauging progress, to cost-effectively manage for biological diversity within working forests and communicate outcomes to stakeholders. Forest certification systems offer a formalized approach for meeting biodiversity goals and demonstrating accomplishments. [ABSTRACT FROM AUTHOR]

• Plantations had lower bird alpha diversity than native grasslands and forests. • Native environments showed higher within-beta diversity than plantations. • Plantations promoted biotic homogenization across the landscape. • Generalists and some forest birds occurred extensively across plantations. • Management for grassland bird conservation needed at the landscape-level. Establishing commercial tree plantations in native grassland ecosystems introduces a different structural and functional vegetation cover type, with expected implications for biodiversity. To better understand biodiversity responses to afforestation, we conducted a resource-use study with birds as a focal group, during the 2013–2014 breeding season in the Northern Campos grasslands of Uruguay. We sampled birds in native environments and plantations of loblolly pine (Pinus taeda) and flooded gum (Eucalyptus grandis) at different rotation stages. We recorded 103 species during 1,573 visits (10-min, 50-meter radius point counts) to 570 stratified sampling units. Native grasslands and forests exhibited greater diversity and had greater variability in species composition than structurally homogeneous plantations. Avian communities in plantations had distinct species combinations and relative abundances not found in native conditions. Avian communities in older plantations were more similar to native forests while those of newly-planted stands were more like grasslands. However, plantations were dominated by habitat generalists and some forest-dependent species, with negligible use by grassland specialist birds. Our results suggest the best conservation opportunities for grassland-dependent birds in afforested systems of the Campos of Uruguay may depend on diverse landscape-level measures rather than stand-level management practices. Albeit our research constituted a comprehensive assessment of bird taxonomic alpha and beta diversity, research on complementary diversity facets and multi-scale resource selection and demographic studies are needed to better understand the fitness implications for conserving and managing grassland birds in afforested landscapes. [ABSTRACT FROM AUTHOR]

Abstract: High yield commercial forests are an important source of fiber for global forest product needs and the southeastern United States is a key region for global wood supply needs with intensively managed pine stands (Pinus spp.) an important component of forested landscapes in this region. Concern has arisen over possible effects of stand establishment practices on vegetation communities within commercial forests, particularly relative to use of herbicides and burning. Therefore, we examined response of plant communities to site preparation within intensively managed pine stands in eastern Louisiana, USA that were either prescribe burned (PF; n =5) or treated with a combination of herbicides (imazapyr and triclopyr) and prescribe burned (PFH; n =5) during 2002. We used 5m line intercepts (n =10 per stand) to quantify species richness, diversity, and relative abundance of plant species for 3 years post-treatment (2003–2005) with a repeated measures analysis of variance. We documented 80 genera or species of plants and neither species richness nor diversity differed between treatments. Site preparation with PFH appeared to promote development of an herbaceous plant community and reduced relative abundance of woody plants, whereas PF-treated sites were dominated by woody vegetation. Our results demonstrate that different plant communities result from PF and PFH site preparation and may place stands on different successional trajectories. We suggest PFH site preparation may increase availability of early successional vegetation associations on managed forest landscapes and may extend the time stands stay in this successional stage. However, increased crop tree growth from site preparation may shorten open canopy conditions. [Copyright &y& Elsevier]

Bats likely incorporate multi-scale criteria when selecting roost sites, which may change across different landscapes. During summers 2002 and 2003, we used radiotelametry to investigate day-roost selection of evening bats (Nycticeius humeralis) at multiple scales in mature longleaf (Pinus palustris: natural) and intensively managed loblolly pine (P. taeda; managed) landscapes in the Gulf Coastal Plain of Georgia, USA. We used Akaike's Information Criterion (ARC) to evaluate models describing roost-site selection at the tree, plot, stand, and landscape scales. Evening bats on the natural site selected day-roosts based on tree, plot, and landscape characteristics, but bats on the managed site selected day-roosts only at the tree and plot scale. We hypothesize that greater availability of roosting structures (i.e., abundant large trees and snags) throughout the natural site allowed evening bats to select day-roosts that had favorable landscape characteristics (i.e., closer to water and foraging sites), possibly providing benefits from reduced commuting costs. On the managed site, the relatively young age structure of stands resulted in less-abundant roosting structures throughout the landscape, resulting in selection only at the tree and plot scales. Evening bats appeared to select day-roosts that provide energetic benefits when landscape conditions permitted, however, replicated studies are needed to examine the relationship between energetics and roost availability. Land management on pine landscapes of the southeastern United States that promotes large trees, retention of snags, and an open midstory appears to provide abundant roost structures for evening bats. On managed landscapes, roost sites for evening bats may be provided by retention of forked-topped pines in managed stands and by allowing maturation and senescence of trees in set-aside areas, such as streamside management zones, to promote snag and cavity formation. [ABSTRACT FROM AUTHOR]

Forest managers are increasingly expected to incorporate biodiversity objectives within forest landscapes devoted to timber production. However, reliable data on which to base management recommendations for bats within these systems are extremely limited. Although the red bat (Lasiurus borealis) is a widespread common species in temperate forests of North America, little is known of its ecology within intensively managed pine (Pinus spp.) forests of the southeastern United States. Therefore, we investigated size of foraging areas and habitat use by red bats during summer 2000 and 2001 in an intensively managed pine landscape in east-central Mississippi, USA. We captured bats using four-tier mist nets placed over water and attached radiotransmitters to red bats. Radiotagged red bats (n = 16 used habitat types randomly at the study area and foraging area stale. Mean size of foraging areas and mean maximum distance traveled between diurnal roosts and foraging locations were not different (P < 0.05) among adult male, adult female, juvenile male or juvenile females (n = 18). Most foraging areas contained a reliable source of water and all but one diurnal roost was located within foraging areas. Location of diurnal roosts may dictate location of foraging areas. Open canopy conditions in intensively managed pine stands (young, open canopy stands, thinned stands and riparian hardwood stands) likely provide appropriate foraging habitat for red bats. Landscape context may influence size of foraging areas and commuting distances of red bats. Provision of appropriate aged forest stands for diurnal roosts may be the best management action for red bats within intensively managed pine landscapes. [ABSTRACT FROM AUTHOR]

Use of herbicides to control competing vegetation in young forests can increase wood volume yields by 50-150%. However, increasing use of herbicides in forest management has caused widespread concerns among the public and biologists about direct toxicity to wildlife and indirect effects through habitat alteration. Abundant research has indicated that forest herbicide treatments target biochemical pathways unique to plants, do not persist in the environment, and have few toxic effects when operationally applied. Herbicides affect forest biodiversity by creating short-term declines in plant species diversity, altering vegetative structure, and potentially changing plant successional trajectories. For wildlife species, effects vary but generally are short-term. Despite these findings, public opinion against forest herbicides often has limited or restricted their use, likely due to people's values associated with forests and a lack of technical knowledge. Future research efforts on relationships between forest herbicides and biodiversity should address landscape and site-specific issues, be based on rigorous experimental design, be relevant to public concerns, include comparisons of herbicide treatments with alternative treatments excluding herbicides, examine use of chemical mixtures, and determine the social, economic, and possible long-term ecological consequences of treatments. [ABSTRACT FROM AUTHOR]

Forest managers are increasingly expected to incorporate biodiversity objectives within forest landscapes devoted to timber production. However, data on which to base management recommendations for bats within these systems are limited. Although the red bat (Lasiurus borealis) is a widespread and common species in temperate forests of North America, little is known of its ecology within intensively managed pine (Pinus spp.) forests of the southeastern United States. Diurnal roost sites of red bats may be limiting on industrial pine forests due to a lack of large hardwoods within managed stands. Therefore, we investigated selection of day roosts by red bats at multiple spatial scales during June–September 2000 and May–August 2001 in an intensively managed pine landscape in east-central Mississippi, USA. We captured bats using 4-tier mist nets placed over water and attached 0.47–0.54 g radiotransmitters to captured red bats (n = 46). We located day roosts of red bats (n = 141 roosts of 27 bats) for the life of the transmitters. Red bats roosted in 16 species of hardwood trees (70% of day roosts) and loblolly pine (Pinus taeda; 30% of day roosts). In contrast to other studies in the southeastern United States, red bats roosted in pine trees and in midstory hardwood trees. Within thinned pine stands, red bats tended to prefer roost trees with a denser subcanopy and higher basal area as compared to random sites. Stand-level characteristics appeared more important than individual tree characteristics in choice of diurnal roosts. Except for adult males, logistic regression models of roost sites of red bats had high (≥79%) correct classification rates. Day roost site requirements of red bats may exhibit greater plasticity than previously thought. On our study area, intensive forest management appears compatible with diurnal roost needs of this species. [Copyright &y& Elsevier]

State-approved forestry best management practices (BMPs) are a practice or combination of practices that, when properly implemented, effectively prevent or reduce the amount of nonpoint source (NPS) pollution entering waterbodies, such as sediment. Although BMPs are voluntary in most states in the southeastern United States (U.S.), forest landowners operating under the auspices of a forest certification system are required to use BMPs, and forest-certified wood procurement organizations also require loggers who supply them with fiber to use BMPs. Current implementation rates are, on average, 93.6% throughout the southeastern U.S. We conducted a literature review to better understand potential effectiveness of BMPs to conserve aquatic resources and species in the southeastern U.S. Our review focuses on how BMPs reduce NPS pollutants, particularly sediment, fertilizers, and herbicides; how BMPs are monitored throughout the southeastern U.S.; and current implementation rates. Additionally, we discuss how state BMP monitoring programs, coupled with participation in forest certification programs that require routine third-party audits, provide assurance to federal and state agencies that BMPs protect aquatic resources and species. The U.S. Fish and Wildlife Service has recognized that working forests where management activities implement BMPs represent a clear, actionable, and scientifically sound approach for conserving at-risk aquatic species. However, there is a data gap in directly linking BMPs to the conservation of aquatic resources. Given the high diversity of aquatic species in the southeastern U.S., it is important to better understand this potential linkage. [ABSTRACT FROM AUTHOR]

The southeastern U.S. is widely known as a bastion of privately-owned, managed pine (Pinus spp.) forests, comprised primarily of native pine species. The region supports high levels of biodiversity, but also a multi-billion-dollar forest products economy critical to socioeconomic stability of rural areas. We conducted a systematic review of studies focused exclusively on avifaunal associations within privately-owned, managed pine landscapes in the southeastern U.S. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analysis framework to examine all available studies that evaluated aspects of avian diversity, abundance, and community composition across a suite of forest types, stand ages, and forest management practices within southeastern managed pine systems in the last 70 years. We screened 160 records through primary database searches, and 1696 secondary records from supplemental searches and other sources, and identified 103 relevant articles for inclusion. As expected, although there is no single forest management practice that best provides for avian communities, we found practices that: (1) involve prudent site preparation; (2) promote forest thinning and intermediate management practices; (3) provide non-pine vegetative cover; (4) supply fine- and meso-filter resources such as retained snags and coarse woody debris; and (5) promote heterogeneity in cover types, largely enhanced value of southeastern managed pine systems to avian communities. Overall, it appears that avian communities can be best maintained by providing a diverse mosaic of forest conditions in managed pine landscapes. Key research gaps include improving understanding avian population demographics, such as survival, reproduction, and dispersal. [ABSTRACT FROM AUTHOR]

Tree stocking and the associated canopy closure in production forests is often greater than optimal for wildlife that require an open canopy and the associated understory plant community. Although mid-rotation treatments such as thinning can reduce canopy closure and return sunlight to the forest floor, stimulating understory vegetation, wildlife-focused thinning prescriptions often involve thinning stands to lower tree densities than are typically prescribed for commercial logging operations. Therefore, we quantified the accuracy and precision with which commercial logging crews thinned pre-marked and unmarked mid-rotation loblolly pine (Pinus taeda) stands to residual basal areas of 9 (low), 14 (medium), and 18 (high) m2/ha. Following harvest, observed basal areas were 3.36, 1.58, and 0.6 m2/ha below target basal areas for the high, medium, and low basal area treatments, respectively. Pre-marking stands increased precision, but not accuracy, of thinning operations. We believe the thinning outcomes we observed are sufficient to achieve wildlife objectives in production forests, and that the added expense associated with pre-marking stands to achieve wildlife objectives in production forests depends on focal wildlife species and management objectives. [ABSTRACT FROM AUTHOR]

• Privately-owned forests represent important areas for conserving biological diversity. • We evaluated bat occupancy and detection relative to insect and vegetation variables. • Vegetation characteristics and insect abundance combined best explained bat occupancy. • Vegetation structure has a stronger influence on bat occupancy than prey abundance. Site-occupancy of bats in forested landscapes has been linked to vegetation clutter, but clutter alone may not sufficiently explain observed site-occupancy. Abundance of prey likely has a strong influence on habitat use in forest landscapes as well. Therefore, we simultaneously examined influence of insect abundance and vegetation characteristics on bat site-occupancy across 3 pine (Pinus spp.)-dominated landscapes within the southeastern U.S. Coastal Plain. We conducted acoustic surveys and used Akaike's Information Criterion to evaluate plausibility of occupancy and detection models that incorporated vegetation- and insect-related factors. Results indicate that bat site-occupancy was better explained by a combination of vegetation characteristics and insect abundance than either separately, and vegetation structure has a stronger influence than prey abundance. Additionally, our data generally suggest insect taxon is more influential in predicting occupancy than insect size. Management activities on pine-dominated landscapes that simultaneously reduce vegetation clutter and increase insect abundance are likely to benefit resident bat species. [ABSTRACT FROM AUTHOR]

Intercropping switchgrass ( Panicum virgatum ) in existing managed pine ( Pinus spp.) forests potentially can produce a biofuel feedstock without encumbering additional arable land. However, it is not clear how intercropping, which changes understory vegetation composition and structure, may influence rodent communities. Therefore, as part of a broader effort to examine ecological sustainability of an intercropping management system, we investigated whether intercropping switchgrass in intensively managed loblolly pine ( Pinus taeda ) stands affected rodent community structure and population demographics in a managed forest landscape. We conducted seven live-trapping sessions during June–August 2012 on three intensively managed pine stands (control) and three intensively managed pine stands intercropped with switchgrass (treatment). Pine stands intercropped with switchgrass had lower rodent community evenness ( P = 0.02) and diversity ( P = 0.03) than control stands primarily because of greater hispid cotton rat ( Sigmodon hispidus ) abundance in intercropped stands ( P = 0.02). However, there was no treatment effect on cotton rat survival or recruitment. Our results suggest the switchgrass intercropping system in our study influenced rodent community structure via effects on hispid cotton rats during the early successional stage of a loblolly pine stand. [ABSTRACT FROM AUTHOR]