Neighborhood Analyses Of Canopy Tree Competition Along Environmental Gradients In New England Forests

We use permanent-plot data from the USDA Forest Service's Forest Inventory and Analysis (FIA) program for an analysis of the effects of competition on tree growth along environmental gradients for the 14 most abundant tree species in forests of northern New England, USA. Our analysis estimates actual growth for each individual tree of a given species as a function of average potential diameter growth modified by three sets of scalars that quantify the effects on growth of (1) initial target tree size (dbh), (2) local environmental conditions, and (3) crowding by neighboring trees. Potential growth of seven of the 14 species varied along at least one of the two environmental axes identified by an ordination of relative abundance of species in plots. The relative abundances of a number of species were significantly displaced from sites where they showed maximum potential growth. In all of these cases, abundance was displaced to the more resource-poor end of the environmental gradient (either low fertility or low moisture). The pattern was most pronounced among early successional species, whereas late-successional species reached their greatest abundance on sites where they also showed the highest growth in the absence of competition. The analysis also provides empirical estimates of the strength of intraspecific and interspecific competitive effects of neighbors. For all but one of the species, our results led us to reject the hypothesis that all species of competitors have equivalent effects on a target species. Most of the individual pairwise interactions were strongly asymmetric. There was a clear competitive hierarchy among the four most shade-tolerant species, and a separate competitive hierarchy among the shade-intolerant species. Our results suggest that timber yield following selective logging will vary dramatically depending on the configuration of the residual canopy, because of interspecific variation in the magnitude of both the competitive effects of different species of neighbors and the competitive responses of different species of target trees to neighbors. The matrix of competition coefficients suggests that there may be clear benefits in managing for specific mixtures of species within local neighborhoods within stands

Inferring controls on the epidemiology of beech bark disease from spatial patterning of disease organisms

1 Spatial pattern in the distribution and abundance of organisms is an emergent property of collective rates of reproduction, survival and movement of individuals in a heterogeneous environment. 2 The form, intensity and scale of spatial patterning can be used to test hypotheses regarding the relative importance of candidate processes to population dynamics. 3 Using 84 plots across eastern North America, we studied populations of two associated plant parasites, the invasive felted beech scale Cryptococcus fagisuga Lind. and the native Neonectria fungi, which together cause beech bark disease (BBD). 4 We evaluated spatial patterns at the scales of trees within stands, stands within the forest and forests within the landscape to examine four hypothetically important factors in the ecology of the disease: (i) local contagion within stands; (ii) regional contagion, or among patch infection–reinfection dynamics; (iii) variation in host susceptibility linked to genetic and/or environmental heterogeneity; and (iv) climate effects on population growth of BBD organisms. 5 Analyses revealed an unexpected lack of spatial aggregation in BBD populations among trees, stands and forests. This implies that propagule pressure is generally sufficiently high throughout the infested region of North America such that neither trees nor stands are spared from the disease by dispersal limitations of the disease agents. Furthermore, variation in tree and stand level susceptibility has minimal impact on BBD dynamics and climate is not a conspicuous driver of abundance within the core range of BBD.This work was partially supported by the USDA Forest Service Northeastern Research Station, grant 04-JV-11242328-122.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1461-9563/hb2013ab201

The Status of Beech Bark Disease in Northern Hardwood Forests: A Research Update from the Beech Bark Disease Symposium of 2004

Since the 1996 article about Beech Bark Disease in Adirondack forests by Dick Sage appeared in AJES, we have gained some valuable information about effects of the disease on forest structure and wildlife. However, a Lack of public awareness and research funding have Limited the progress in understanding factors affecting spread and severity of the disease, mechanisms of disease resistance, and the future demographics of American beech (Fagus grandi­folia) in our forests. This paper reviews some of the research findings with respect to the effect of the invasive disease complex on forest structure and composition and wildlife populations. We present outcomes of recent research on disease resistance and discuss the application of all this information to silviculture and forest management. We draw heavily on research presented at the Beech Bark Disease Symposium held in Saranac Lake in June 2004. Our hope is to raise awareness about the great impact the disease has already had, and the continued impact it is Liluly to have in the future as it persists in Long affected forests and spreads throughout the range of this stately tree

ZaldForestCarbonCalculatorsSupplement.pdf

Forests play a critical role sequestering atmospheric carbon dioxide, partially offsetting greenhouse gas emissions, and thereby mitigating climate change. Forest management, natural disturbances, and the fate of carbon in wood products strongly influence carbon sequestration and emissions in the forest sector. Government policies, carbon offset and trading programs, and sustainable forestry certification programs make it increasingly important that carbon dynamics are incorporated into forest management decisionmaking. Many analytical tools (which we refer to as forest carbon calculators) have been developed to quantify carbon stores and dynamics in the forest sector, but it can be difficult for potential users to know which carbon calculator(s) may be best for any given application. We review 12 forest carbon calculators, providing a classification and synthesis to assist forest managers, policymakers, and educators. Additionally, we discuss key characteristics missing in existing forest carbon calculators that are needed for current and future forest management decisionmaking.Keywords: forest carbon calculators, carbon sequestration, disturbance, managemen

ZaldForestCarbonCalculators.pdf

Forests play a critical role sequestering atmospheric carbon dioxide, partially offsetting greenhouse gas emissions, and thereby mitigating climate change. Forest management, natural disturbances, and the fate of carbon in wood products strongly influence carbon sequestration and emissions in the forest sector. Government policies, carbon offset and trading programs, and sustainable forestry certification programs make it increasingly important that carbon dynamics are incorporated into forest management decisionmaking. Many analytical tools (which we refer to as forest carbon calculators) have been developed to quantify carbon stores and dynamics in the forest sector, but it can be difficult for potential users to know which carbon calculator(s) may be best for any given application. We review 12 forest carbon calculators, providing a classification and synthesis to assist forest managers, policymakers, and educators. Additionally, we discuss key characteristics missing in existing forest carbon calculators that are needed for current and future forest management decisionmaking.Keywords: forest carbon calculators, carbon sequestration, management, disturbanceKeywords: forest carbon calculators, carbon sequestration, management, disturbanc

Forest Carbon Calculators: A Review for Managers, Policymakers, and Educators

Forests play a critical role sequestering atmospheric carbon dioxide, partially offsetting greenhouse gas emissions, and thereby mitigating climate change. Forest management, natural disturbances, and the fate of carbon in wood products strongly influence carbon sequestration and emissions in the forest sector. Government policies, carbon offset and trading programs, and sustainable forestry certification programs make it increasingly important that carbon dynamics are incorporated into forest management decisionmaking. Many analytical tools (which we refer to as forest carbon calculators) have been developed to quantify carbon stores and dynamics in the forest sector, but it can be difficult for potential users to know which carbon calculator(s) may be best for any given application. We review 12 forest carbon calculators, providing a classification and synthesis to assist forest managers, policymakers, and educators. Additionally, we discuss key characteristics missing in existing forest carbon calculators that are needed for current and future forest management decisionmaking.Keywords: disturbance, management, forest carbon calculators, carbon sequestratio

Forest Management Planning for Tree Farmers - a Practical Decision Support Process in the U.S.

Les auteurs présentent un procédé qui permet de simuler différents scénarios de gestion d'une propriété forestière dans une perspective de rentabilité. La démarche s'appuie sur une étude de cas d'un domaine de 400 hectares en Caroline du Sud partagé entre production forestière et agricole. Elle comporte différentes étapes : définition des objectifs du propriétaire avec toutes les options possibles, caractérisation de la forêt selon des critères quantifiables, intégration des méthodes de gestion répondant aux objectifs fixés, simulation des scénarios retenus grâce au système d'aide à la décision nommé NED mis au point par les auteurs. Projetée sur une quarantaine d'années, la simulation montre la faisabilité de 3 scénarios qui combinent la production ligneuse à d'autres sources de profit comme la production agricole, le tourisme ou la chasse, et permet de réaliser des choix de gestion en conséquence.The authors describe a process for simulating various forest management scenarios for the purposes of assessing profitability. This approach is based on a case study of a 400-hectare estate in South Carolina. It comprises several stages: defining the owner's goals with all the possible options, characterising the forest according to quantifiable criteria, integrating management methods in line with the goals set out, simulating the chosen scenarios using NED, the decision support application developed by the authors. The simulation runs projections over some 40 years, demonstrating the feasibility of 3 scenarios that combine timber production with other sources of profit such as farming, tourist activities and hunting, thereby providing the basis for choosing management options

Appendix A. Tables reporting parameter estimates and two-unit support intervals for the most parsimonious models for each of the 14 target tree species.

Tables reporting parameter estimates and two-unit support intervals for the most parsimonious models for each of the 14 target tree species