Forest Service Research Articles

Towards an objective assessment of tree vitality: a case study based on 3D laser scanning

Key message Analyzing fine branch length characteristics in beech trees using single-tree QSMs derived from laser scanning reveals insights into drought-induced changes in vitality, which include branch shedding and reduced shoot growth. Abstract Climate change causes increasing temperatures and precipitation anomalies, which result in deteriorations of tree health and declines in ecosystem services of forests. It is therefore crucial to monitor tree vitality to preserve forests and their functions. However, methods describing tree vitality in situ are lacking reproducibility or are too laborious. Thus, we tested a laser-scanning based approach, assuming that an objective measurement of a tree’s outer shape should reveal changes according to tree vitality. QSMs of similarly sized beech trees from stands with varying degrees of drought damage were used. Absolute and relative fine branch lengths, their ratio to lower order branches’ lengths and their progressions over relative height were targeted to identify fine branch dieback and reduced growth. The absolute fine branch length was significantly lower for less vital beech trees, especially within the upper crown, leading to a less top-heavy vertical distribution of fine branches and a reduced fine-to-base order branch length ratio. Hence, height-dependent characteristics of fine branch lengths differed between vitalities. We conclude that using fine branch length characteristics derived from QSMs can be helpful in vitality assessments of beech trees. Still, uncertainties with regard to the plotwise assessment and problems with QSM quality are present.

A Review of Forest Ecosystem Services and Their Spatial Value Characteristics

Forests provide a variety of resources and benefits, but only a few, such as timber, are traded on the markets. Ecosystem service valuation is a method for quantifying the non-market benefits of forests to understand the full costs of forest management. This review examines the forest ecosystem service valuations over the past 20 years, with a particular focus on their spatial modeling. The literature review method is designed to provide a systematic, explicit, and reproducible outcome concerning the valuations of forest ecosystem services and the contextual setting of these valuations. The findings suggest that there is a huge variation in the values reported for similar ecosystem services but that carbon sequestration, recreation in forests, and hydrological services, such as watershed protection and flood prevention, are the ecosystem services that are consistently valued highly in the reviewed studies. In the last ten years, studies have more frequently modeled ecosystem services in spatial terms.

Smart Tourism Development for Recreation in Pesanggrahan Sangga Buana Urban Forest, South Jakarta

Urban forest is a form of green open space in the urban area. The use of information and communication technology based on smart tourism is an important factor in providing facilities for recreational areas. This research aims to formulate smart tourism-based development at PSBUF for recreation based on resources, management and preferences of visitors and the surrounding community. Data collection methods used were literature studies, field observation, questionnaires, and interviews. The data analysis used were qualitative, quantitative descriptive, and SWOT. Pesanggrahan Sangga Buana Urban Forest (PSBUF) has the potential to develop smart tourism-based facilities for recreation. Standard recreational facilities are available in the form of prayer rooms, toilets, gazebos, jogging tracks, parking lots, badminton courts and football fields. Urban forest management is carried out by EFG Sangga Buana with supervision by the DKI Jakarta Parks and Urban Forest Service. EFG Sangga Buana strives to preserve the environment in the DKI Jakarta area with facilities that do not disturb the surrounding ecosystem. The existence of jogging tracks and sports fields is still lacking. The biggest motivation for visiting the urban forest is to refresh the mind from daily boredom. Public facilities that are really needed are rubbish bins. Respondents need for smart tourism facilities in the form of CCTV is the highest. Recommendations for the development of facilities are optimizing potential, maximizing management cooperation, increasing PSBUF promotions, and optimizing coordination between managers.

A Five-Step Framework for Creating Forests for the Future

Changing environmental conditions, disturbances, and escalating demands for forest ecosystem services require foresters to restore present forestlands with new forest generations that will exhibit ecological integrity, diversity, high adaptive capacity, and the ability to provide essential ecosystem services. Establishing such forests requires careful consideration of the forest landscape and site dynamics. In pursuit of these requirements, we developed a novel framework that enables the restoration of forest sites and promotes the desired features of the forest complex at the same time. This framework was designed with the methods of system engineering and was organized in the same way as the forest planning process. It was tested in the habitat type of Illyrian Fagus sylvatica forests belonging to the Natura 2000 network. The environmental, vegetation, and site conditions were investigated via field inspections, available forest management plans, and simple GIS analyses. Additionally, we established a seminatural stand composed of European beech, sessile oak, sycamore maple, silver fir, and some wild fruit tree species. The survival of planted species was assessed using census and simple random sampling, the performance of provenances by the Student’s test, while microhabitat factors were explored by a one-way ANOVA. The survival rate of key species was estimated to be 55.6%, while that of fruit species was estimated to be 94.5%. Our framework demonstrated satisfactory performance and contained sufficient benchmarks to facilitate consistent decision-making. In the discussion, we elucidate the framework’s primary features and attributes of the mixed stand, where we also expose some open issues to be addressed in the future.

Minding the Science–Practice Gap to Reach the Goals of Sustainable Recreation Research

Scholars featured in a recent special issue of the Journal of Park and Recreation Administration and others have noted that public lands management has yet to integrate sustainable recreation policy and practice (Cerveny et al., 2022, p. 1). Additionally, there is growing recognition that inter-agency and scientist-citizen collaboration are needed to achieve this goal. In this commentary, we offer an example of minding the science-practice gap through cocreating research. Specifically, we describe how scientists from the US Forest Service and the University of California, Davis, and practitioners from the Los Angeles-based organization Outward Bound Adventures (OBA) operationalized ten essential characteristics of research (DePoy & Gitlin, 2020) in the development of a research proposal and implementation of a study on urban Black, Indigenous, and People of Color (BIPOC) youth perspectives of the outdoors.

Backfire: the settler-colonial logic and legacy of Smokey Bear

ABSTRACT Since the 1940s, the United States Forest Service’s (USFS) national fire suppression efforts have been bolstered by a public-facing ad campaign led by the Ad Council, most notably through the iconic rise of Smokey Bear. The consequences of decades of strict fire suppression, promulgated and solidified by this highly successful campaign, have been ecologically disastrous, and especially detrimental for fire-dependent Indigenous communities and ecosystems. Scholars have examined the Smokey campaign’s racialized, nationalist discourse, yet none have grappled with the campaign’s settler colonial logic, itself replete with gendered exclusion and speciesism. In this article, we combine intersectional theoretical frameworks with settler colonial and Indigenous studies to carry out a systematic content analysis of 201 unique campaign documents. We demonstrate how the campaign’s production of the careful citizen – one rooted in mid-to-upper class, settler masculinity – hinges on interlocking narratives of Indigenous erasure, low-class criminality, and the helpless victimhood of women and more-than-human species.

Transcription factor CgSte12 regulates pathogenicity by affecting appressorium structural development in the anthracnose-causing fungus Colletotrichum gloeosporioides.

Colletotrichum gloeosporioides is the causal agent of poplar anthracnose, which induces major economic losses and adversely affects the ecosystem services of poplar forests. The appressorium serves as a penetration structure for many pathogenic fungi, including C. gloeosporioides. The production of mucilage and the formation of penetration pegs are critically important for the appressorium-mediated penetration of host tissues. We previously found that CgPmk1 is a key protein involved in appressorium formation, penetration, and pathogenicity. Although CgSte12, which is a transcription factor that functions downstream of CgPmk1, regulates the formation of penetration pegs, its role in C. gloeosporioides appressorium development and pathogenicity has not been elucidated. Here, we developed C. gloeosporioides CgSTE12 mutants and characterized the molecular and cellular functions of CgSTE12. The results showed that mycelial growth and morphology were not affected in the CgSTE12 knockout mutants, which produced normal melanized appressoria. However, these mutants had less mucilage secreted around the appressoria, impaired appressorial cone formation, and the inability to form penetration pores and pegs, which ultimately led to a significant loss of pathogenicity. Our comparative transcriptome analysis revealed that CgSte12 controls the expression of genes involved in appressorium development and function, including genes encoding cutinases, NADPH oxidase, spermine biosynthesis-related proteins, ceramide biosynthesis-related proteins, fatty acid metabolism-related proteins, and glycerophospholipid metabolism-related proteins. Overall, our findings indicate that CgSte12 is a critical regulator of appressorium development and affects C. gloeosporioides pathogenicity by modulating the structural integrity of appressoria.

Soil and climate‐dependent ingrowth inference: broadleaves on their slow way to conquer Swiss forests

Forests provide essential ecosystem services that range from the production of timber to the mitigation of natural hazards. Rapid environmental changes, such as climate warming or the intensification of disturbance regimes, threaten forests and endanger forest ecosystem services. In light of these challenges, it is essential to understand forests' demographic processes of regeneration, growth, and mortality and their relationship with environmental conditions. Specifically, understanding the regeneration process in present‐day forests is crucial since it lays the foundation for the structure of future forests and their tree species composition. We used Swiss National Forest Inventory (NFI) data covering vast bio‐geographic gradients over four decades to achieve this understanding. Trees that reached a diameter at breast height of 12 cm between two consecutive NFI campaigns were used to determine regeneration and were referred to as ingrowth. Employing three independent statistical models, we investigated the number, species, and diameter of these ingrowth trees. The models were subsequently implemented into a forest simulator to project the development of Swiss forests until the mid‐21st century. The simulation results showed an ingrowth decrease and a shift in its species composition, marked by a significant reduction in Norway spruce Picea abies and concurrent increases in broadleaves. Nevertheless, the pace of this change towards climatically better adapted species composition is relatively slow and is likely to slow down even further as ingrowth declines in the future, in contrast to the fast‐changing climatic conditions. Hence, support through adaptive planting strategies should be tested in case ingrowth does not ensure the resilience of forests in the future. We conclude that since the regeneration of forests is becoming increasingly challenging, the current level at which ecosystem services are provided might not be ensured in the coming decades.

Constraints on Mechanical Fuel Reduction Treatments in United States Forest Service Wildfire Crisis Strategy Priority Landscapes

Abstract The USDA Forest Service recently launched a Wildfire Crisis Strategy outlining objectives to safeguard communities and other values at risk by substantially increasing the pace and scale of fuel reduction treatment. This analysis quantified layered operational constraints to mechanical fuel reduction treatments, including existing vegetation, protected areas, steep slopes, and administrative boundaries in twenty-one prioritized landscapes. Results suggest that achieving the objective to treat 20%–40% of high-risk area is unlikely in most landscapes under a business-as-usual approach to mechanical fuel reduction treatments. Increased investment in steep-slope systems and expanded road access opens sufficient acreage to meet treatment objectives in eighteen of twenty-one priority landscapes. Achieving treatment objectives in the remaining three landscapes will require both increased investment to overcome physical constraints and navigating administrative complexities within reserved land allocations to implement fuels treatments at the pace and scale needed to moderate fire risk to communities. Study Implications: Legal, operational, and administrative factors have hindered the implementation of proposed wildland fire risk reduction management actions. Investing in steep-slope systems, expanding use of temporary roads, and revising administrative rules to allow for appropriately tailored mechanical thinning in special conservation areas are possible ways to meet fuel reduction treatment objectives of the USDA Forest Service Wildfire Crisis Strategy in twenty-one landscapes across the western United States. Broadening the land base available for mechanical treatment allows for flexibility to develop treatment plans that optimize across the multiple dimensions of effective landscape-scale fuel treatment design and restore fire as a key ecosystem process.

Mapping ecosystem service temporal trends: a case study of European wood potential, supply and demand between 2008 and 2018

Wood is one of the key forest Ecosystem Services (ES) of growing ecological, social and economic importance; therefore, we need more precise information about its long-term usage. To achieve this, it is necessary to examine the spatio-temporal aspects of wood ES potential, supply and demand. In this study, we analyse spatio-temporal patterns of wood ES supply and demand at continental, national and regional scales to identify areas of increasing and decreasing supply and demand levels in Europe. In addition, we present background information about the potential of European forests to provide wood ES and its relationship to supply and demand. Our results showed that the overall European wood supply and demand as well as the wood ES potential were characterised by increasing trends. Furthermore, this increase was also regional, particularly in central and northern Europe. This study demonstrates not only the significance of spatio-temporal data in ES mapping, but also the importance of considering a broader range of components of the ES cascade model when assessing change. Our research has shown that potential, supply and demand can all increase in the same area, but also that low supply and demand do not guarantee wood potential growth. In addition, we found that a broad scale assessment helps to identify more general patterns and trends, but analysing data at a more accurate scale provides more comprehensive insights for identifying areas that may require targeted action for sustainable forest management.

Restoring forest ecosystem services through trait-based ecology

Restoration is moving towards a more mechanistic approach that emphasizes restoration of ecosystem services. Trait-based approaches provide links between species identity and ecosystem functions and have been suggested as a promising way to formally integrate ecosystem services in the design of restoration programs. While practitioners have been routinely using informal knowledge on plant traits in their practices, these approaches are underutilized as operationalization remains challenging. The goal of this paper is to provide guidance for applied scientists and restoration practitioners looking to apply a trait-based approach to restore forest ecosystems. We present a five-step framework: 1) selection of services to be restored, 2) trait selection, 3) data acquisition, 4) analytical planning, and 5) empirical testing and monitoring. We use three Canadian case studies to illustrate the applicability of our framework and the variety of ways trait-based approaches can inform restoration practices: 1) restoration of urban woodlots after an insect outbreak, 2) restoration of a smelter damaged landscape surrounding an urban area, and 3) reclamation of remote upland forests after oil and gas related disturbances. We describe the major mechanisms and traits that determine vegetation effects on ecosystem services of importance in each case study. We then discuss data availability, methodological constraints, comparability issues, analytical methods, and the importance of empirical testing and monitoring to ensure realistic prediction of service restoration. By outlining issues and offering practical information, we aim to contribute to a more robust use of traits in ecological restoration.

Quantifying soil erosion and soil organic carbon conservation services in indian forests: A RUSLE-SDR and GIS-based assessment

Indian forests, having sixteen types of vegetation, provide various ecosystem services. Forests reduce water erosion of soil, reduce floods and conserve low river flow during dry seasons. Present study estimated annual sedimentation, texture, soil organic carbon control service of forests of India using the Revised Universal Soil Loss Equation (RUSLE) and Sediment Delivery Ratio (SDR) approach through GIS technique along with identifying important drivers responsible for erosion in forests. The soil erosion control service was based on five factors viz., rainfall erosivity, soil erodibility, slope, crop management, conservation practice factor and SDR across the various forest dominated river basins. Geo-detector modelling was performed to evaluate environmental drivers responsible for soil erosion. Valuation of soil control service of the India’s forests was estimated based on damage and replacement cost method. Annual soil loss rate was maximum in Tropical Thorn Forest and in Ganga River basin. Maximum sediment control and SOC conservation against the soil erosion control service by India’ forests were due to Tropical Dry Deciduous Forest with a total annual sedimentation control and SOC conservation of 33,056,560 tonnes and 3,31,115.06 tonnes, respectively. The conservative estimate of the economic value of soil conservation service by the forests of India was US$ 535.6 M with an average of 4.40 US$ ha−1 and a maximum share of value for Tropical Dry Deciduous Forest i.e. 294.18 million US$ and average maximum value for Littoral and Swamp Forest (28.91 US$ ha−1). The soil erosion in Tropical and Sub-tropical Forest was influenced by the interactive effects between NDVI and Bulk Density. In contrast, soil erosion in the temperate and alpine area was influenced by anthropogenic activity in combination with climatic factors. Present study accounts the role of India’s forests for the soil conservation service and may provide inputs to implement forest and reservoir management strategies besides providing information for Integrated Watershed management and Catchment Treatment Plans.

Climate change could negate U.S. forest ecosystem service benefits gained through reductions in nitrogen and sulfur deposition

Climate change and atmospheric deposition of nitrogen (N) and sulfur (S) impact the health and productivity of forests. Here, we explored the potential impacts of these environmental stressors on ecosystem services provided by future forests in the contiguous U.S. We found that all stand-level services benefitted (+ 2.6 to 8.1%) from reductions in N+S deposition, largely attributable to positive responses to reduced S that offset the net negative effects of lower N levels. Sawtimber responded positively (+ 0.5 to 0.6%) to some climate change, but negatively (− 2.4 to − 3.8%) to the most extreme scenarios. Aboveground carbon (C) sequestration and forest diversity were negatively impacted by all modelled changes in climate. Notably, the most extreme climate scenario eliminated gains in all three services achieved through reduced deposition. As individual tree species responded differently to climate change and atmospheric deposition, associated services unique to each species increased or decreased under future scenarios. Our results suggest that climate change should be considered when evaluating the benefits of N and S air pollution policies on the services provided by U.S. forests.

Aboveground biomass stocks of species-rich natural forests in southern China are influenced by stand structural attributes, species richness and precipitation

Forests, the largest terrestrial carbon sinks, play an important role in carbon sequestration and climate change mitigation. Although forest attributes and environmental factors have been shown to impact aboveground biomass, their influence on biomass stocks in species-rich forests in southern China, a biodiversity hotspot, has rarely been investigated. In this study, we characterized the effects of environmental factors, forest structure, and species diversity on aboveground biomass stocks of 30 plots (1 ha each) in natural forests located within seven nature reserves distributed across subtropical and marginal tropical zones in Guangxi, China. Our results indicate that forest aboveground biomass stocks in this region are lower than those in mature tropical and subtropical forests in other regions. Furthermore, we found that aboveground biomass was positively correlated with stand age, mean annual precipitation, elevation, structural attributes and species richness, although not with species evenness. When we compared stands with the same basal area, we found that aboveground biomass stock was higher in communities with a higher coefficient of variation of diameter at breast height. These findings highlight the importance of maintaining forest structural diversity and species richness to promote aboveground biomass accumulation and reveal the potential impacts of precipitation changes resulting from climate warming on the ecosystem services of subtropical and northern tropical forests in China. Notably, many natural forests in southern China are not fully stocked. Therefore, their continued growth will increase their carbon storage over time.

IMPACT OF FOREST FIRES ON PORTUGUESE FOREST ECOSYSTEM AND ITS NATIONAL EMISSIONS BUDGET

The study highlights the significance of the forestry industry in Portugal, and delves into the economic, social, and environmental ramifications of forest fires on this vital sector. With a specialization in forest services, the country's healthy and sustained growth is heavily reliant on this sector. The study is a literature review analysis of carbon sink-source relationships and related uncertainty in the Portuguese forest ecosystem. We found wide literature research that Portugal lost 4% of its total tree cover due to forest fires in 2016-2017. The study concludes that the drought and forest fires suffered by the country throughout the years have had a considerable impact on the national emissions budget. Forest fires have wielded a significant impact on the nation's overall carbon emissions, representing 10% during the years with the highest incidence and averaging 2.7% over 25 years. Prior to 2014, the country was making significant progress towards achieving its National Plan on Climate Change (PNAC) 2020 reduction target, with emissions projected to fall between 18-23% below 2005 levels. These factors are putting country in a non-compliance position with the PNAC 2020 commitment target (which is the same target as for the Kyoto Protocol 2nd Commitment Period).

Analysis of Wildfire-Damaged Buildings Using Spatial Information: The Case of the 2023 Gangneung Wildfire

In Korea, several policies and previous studies have focused on forest fire prevention; however, research on the characteristics of building damage caused by wildfires is insufficient. This study investigated a large wildfire that occurred in Gangneung on April 11, 2023, and analyzed the characteristics of the damaged buildings. Furthermore, several discussion points related to building damage due to wildfires are presented through a comparison with previous research. First, because piecemeal measures have limitations in reducing damage to buildings, comprehensive and organic measures are needed, such as supplementing building regulations, managing the surrounding environment, installing damage-reduction facilities, and securing access to firefighting services. Second, although vulnerable infrastructure (fire stations, roads, etc.) must be expanded, additional research is needed focusing on actual cases. Third, because cooperation between various agencies and organizations such as the Korea Forest Service and the National Fire Agency is important in responding to wildfires, systematic improvements are required to make quick and accurate decisions.

Combining terrestrial lidar with single line transects to investigate geomorphic change: A case study on the Upper Verde River, Arizona

The Upper Verde River in northern Arizona, USA is a vital resource for the wildlife and humans that rely on its waters. We characterize the riparian corridor topography using terrestrial laser scanner (TLS) data from 2021 to 2022. We also quantify geomorphic changes associated with human and climate-driven alterations in river flow and vegetation changes by combining the contemporary lidar surveys with legacy measurements from single line geomorphology transects measured by the United States Forest Service (USFS) in 2009. Seventeen plots along the Upper Verde River were surveyed with the TLS and the data were coregistered within individual plots with a Root Mean Square Error of <0.03 m among scan positions. Digital Elevation Models (DEM) were derived for each plot from the TLS data at 10 cm resolution and compared to the 2009 USFS cross-section data to quantify elevation changes. In areas with statistically significant change, we detected maximum changes in elevation due to erosion and deposition of −0.37 m and + 0.97 m, respectively. Topographic changes over the 13-year period were predominately aggradation and associated with sediment deposition, which we hypothesize might have resulted from altered river flow and vegetation encroachment. This study also demonstrates a quantitative and statistical methodology to fuse traditional single line cross-section data with contemporary lidar data to quantify geomorphic change. The novel approach demonstrated here is broadly applicable to natural resource managers for integrating and contextualizing legacy topographic data for understanding past, present, and future landscape and habitat changes.

Creating Boundary Objects Supports Knowledge Co-development Processes: A Case Study Evaluation from the Colorado Front Range

Abstract This qualitative case study evaluates manager and researcher perceptions of the impact of a place-based, collaborative knowledge co-development process and examines the outcomes of that co-development for changes to management approaches. The USDA Forest Service (Forest Service) Rocky Mountain Research Station General Technical Report 373 (GTR-373) is a codeveloped science synthesis that functions as a boundary object providing a framework for planning, designing, and implementing management action for restoration of ponderosa and dry mixed-conifer forests. The process of creating and socializing the GTR-373 framework fostered continual knowledge exchange and engagement between researchers and managers across different organizations and levels of decision-making. This built trust in the information, improved justification for management action, developed a common foundation for cross-boundary implementation, and increased communication. The framework has been applied across jurisdictions and has been used as a foundational tool for training staff and designing projects. However, adapting the GTR-373 framework across scales remains challenging. Study Implications: This qualitative case study evaluates a co-development process in which researchers and managers from multiple organizations and agencies collaborated to produce a science-informed restoration framework to support forest management on the Colorado Front Range (GTR-373). The process built trust, improved justification for management action, developed a common foundation for implementation, and increased communication. However, cross-boundary management across spatial scales remains challenging, and managers interpret information through organizational mandates and site-specific context. Sustained collaboration between researchers and land managers can help make science actionable and relevant at the appropriate scale for planning and management across expertise and jurisdictional boundaries.

Feasibility of constructed soils for tree planting – A pilot study in New York City

Constructed soils are soils that are created with a mixture of various materials. An innovative soil exchange program - the Clean Soil Bank (CSB) in New York City allows recycling of clean glacial outwash sediments excavated from depth at construction sites. One previous study showed that soils constructed from CSB sediment and compost can effectively support crop growth in community gardens, but no research has been conducted on its potential usage as a medium for tree growth. Moreover, biochar has been used to improve soil quality, but its efficacy for street trees incorporated into constructed soils has largely not been quantified in the field. The objective of this project was to evaluate the feasibility of using soils constructed from the CSB and compost for tree planting and to investigate the impact of biochar on tree performance. Thirty-six trees of two species (Maackia amurensis and Zelkova serrata) were planted in 2019, on the sidewalks of a residential-business neighborhood in Bronx, New York. Each tree pit contains one of three soil types: type A - existing and purchased topsoil mixed with 33% compost and biochar, type B - CSB sediment mixed with 33% compost, and type C - CSB sediment mixed with 33% compost and biochar. Soil samples were collected in 2019 (before planting) and in 2021. Tree health assessments were conducted in September 2020 and July 2021 using a protocol developed by the USDA Forest Service. Other tree health parameters collected include diameter at breast height (DBH), crown diameter, tree height, photosynthetic capacity, and foliar chemistry. Significant differences in bulk density, water holding capacity, and K, Fe, and Zn concentrations were found among the three soil types. However, comparison of tree performance and foliar chemistry showed no systematic differences among the three soil types. The results indicate that CSB sediment mixed with compost can be an effective replacement for purchased topsoil for tree growth. No evidence was found that biochar provides additional benefits to street tree performance. Considering the abundant availability of glacial outwash sediment at low cost to the city, as well as access to locally produced compost, constructed soils can be a reliable source of material for urban forestry programs.

Comparative assessment of woody species diversity, structure and carbon stock of PFM and Non-PFM forests and its implication for REDD+ in Ethiopia

Maintaining forest biodiversity and carbon sequestration potential of forest resources enhances the provision capacity of forest ecosystem services. Experience from around the world and in Ethiopia has shown that shifting forest management from state-centred to community-centred arrangement can result in a better forest stock. Therefore, this study examined the status of woody species diversity, regeneration and total living biomass carbon stock of forests under participatory forest management (PFM) and the adjacent state managed non-participatory forest management (Non-PFM) in South eastern Ethiopia and implications to REDD+. Data were collected from 89 (44 PFM and 45 Non-PFM) nested circular plots from four PFM and three Non-PFM selected forest sites with transects laid systematically. Tree DBH and height were measured, the number of saplings, seedlings, mature trees were counted and species names were recorded. Woody species diversity was estimated using shannon, simpson, and evenness diversity indices. A total of 29 and 23 woody species were recorded in PFM and Non-PFM forests, respectively. Woody species diversity did not show significant difference between PFM and Non-PFM forests but it was relatively higher in PFM forest. The density per hectare of seedlings, sapling and mature trees were significantly greater in PFM forest than in Non-PFM forest. The mean aboveground biomass carbon stock of PFM forest (225.50±26.54) was significantly greater than that of the Non-PFM (156.24±15.72) forest. Hence, managing forests through participatory approaches contributes to the enhancement of sustainable management and climate change mitigation potentials through reducing emission from deforestation and forest degradation.