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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]

In heterogeneous forest landscapes prone to wildfires, accurate classification of the fire regime beyond direct observations and records is difficult. This is in part due to the methods used to reconstruct historical fires in complex, heterogeneous landscapes with varying fire severities. Mixed-severity fire regimes, defined as variations in wildfire severity over time and/or space, have important implications for ecosystem functioning and forest management. Fire event detection is used to reduce uncertainties in historical tree-ring proxy records. The number of fire events considered in fire regime classification varies based on detection criteria (filters) that are researcher-selected, such as number of trees or plots recording fire. Here we analyzed the sensitivity of fire regime classification to common detection criteria in a mixed-severity fire regime in the eastern foothills of the Rocky Mountains, Alberta, Canada. We found that detection criteria bias records toward high-severity events and against potentially ecologically significant low-severity fires in mixed-severity regimes, ultimately classifying them as higher severity. We conclude that detection criteria methods must address the scale that is relevant to the ecological or management questions being addressed. [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]

Abstract: Pine plantations in the southeastern United States are often created using site preparation treatments to alleviate site conditions that may limit survival or growth of planted seedlings. However, little is understood about how site preparations affect longleaf pine (Pinus palustris P. Miller) seedlings planted on wet sites. In a 2-year study (2004 and 2005) on poorly drained, sandy soils of Onslow County, North Carolina, we examined the effects of common site preparation treatments on microsite conditions and quantified relationships between microsite conditions and longleaf pine seedling survival and growth. Treatments used in the study included site preparations designed to control competing vegetation (chopping and herbicide) combined with those that alter soil conditions (mounding and bedding). During both years, mounding and bedding treatments reduced the amount of moisture within the top 6cm of soil and increased soil temperatures when compared to flat planting (p <0.001). Soil moisture was inversely related to seedling mortality in 2004 (r 2 =0.405) and inversely related to root collar diameter in 2005 (r 2 =0.334), while light was positively related to root collar diameter in 2005 (r 2 =0.262). Light availability at the seedling level was highest on treatments that effectively reduced surrounding vegetation. Herbicides were more effective than chopping at controlling vegetation in 2004 (p <0.001) and 2005 (p =0.036). Controlling competing vegetation, especially shrubs, was critical for increasing early longleaf pine seedling growth. [Copyright &y& Elsevier]

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]