Treesearch

Increasing the frequency of resistance to the non-native fungus Cronartium ribicola (causative agent of white pine blister rust, WPBR) in limber pine populations is a primary management objective to sustain high-elevation forest communities. However, it is not known to what extent genetic disease resistance is costly to plant growth or carbon economy. In this study, we measured growth and leaf-level physiology in (1) seedling families from seed trees that have previously been inferred to carry or not carry Cr4, the dominant R gene allele conferring complete, gene-for-gene resistance to...

Following wildfire, forest managers are challenged with meeting both socioeconomic demands (e.g., salvage logging) and mandates requiring habitat conservation for disturbance-associated wildlife (e.g., woodpeckers). Habitat suitability models for nesting woodpeckers can be informative, but tests of model transferability are needed to understand how broadly models developed at one location can be applied to inform post-fire forest management at other locations. We developed habitat suitability models and tested their transferability for 2 disturbance-associated woodpecker species, Black-back...

Recovery of ecological communities following disturbance is a central theme of ecology and may be mediated by priority effects, in which the species or individuals that first arrive at a site alter the biotic or abiotic environment in ways that affect the establishment and growth of species or individuals that arrive at a later time. Priority effects are common, influencing species distributions and how ecosystems function (Connell and Slatyer 1977; Werner et al. 2016). Ubiquitous in arid and semi-arid regions worldwide, biological soil crusts (Figure 1) contribute to a large number of...

The use of remote sensing in ecosystem management has transformed how land managers, practitioners, and policymakers evaluate ecosystem loss, gain, and change at multiple spatial and temporal scales. Less developed is the use of these spatial tools for planning, implementing, and evaluating ecosystem restoration projects and especially so in multifunctional landscapes. We use a case study approach in a multistakeholder tropical dryland restoration project to highlight the potential of remotely sensed products to quantitatively and economically guide often conflicting restoration priorities...

We measured pH, cations, nutrients, and total organic carbon (TOC) over 3 years to examine weekly to monthly variability in porewater chemistry depth profiles (0–3.0 m) in an ombrotrophic bog in Minnesota, USA. We also compared temporal variation at one location to spatial variation in depth profiles at 16 locations across the bog. Most solutes exhibited large gradients with depth. pH increased by two units and calcium concentrations increased over 20 fold with depth, and may reflect peatland development from minerotrophic to ombrotrophic conditions. Ammonium concentrations increased...

Conspecific density may contribute to patterns of species assembly through negative density dependence (NDD) as predicted by the Janzen-Connell hypothesis, or through facilitation (positive density dependence; PDD). Conspecific density effects are expected to be more negative in darker and wetter environments due to higher pathogen abundance and more positive in stressful, especially dry, environments (stress-gradient hypothesis). For NDD to contribute to maintaining diversity, it should be apparent at the community-wide scale as a negative correlation between seedling recruitment, growth...

This periodic resource update provides an overview of forest resources in North Carolina based on an inventory conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program at the Southern Research Station in cooperation with the North Carolina Forest Service. Data estimates are based on field data collected using the FIA annualized sample design and are updated yearly. The estimates presented in this update are for the measurement year 2014 with comparisons made to data reported in 2013.

Fungal species with a broad distribution may exhibit considerable genetic variation over their geographic ranges. Variation may develop among populations based on geographic isolation, lack of migration, and genetic drift, though this genetic variation may not always be evident when examining phenotypic characters. Fomitopsis pinicola is an abundant saprotrophic fungus found on decaying logs throughout temperate regions of the Northern Hemisphere. Phylogenetic studies have addressed the relationship of F. pinicola to other wood-rotting fungi, but pan-continental variation within F....

The southeastern United States contains expansive and diverse forests that provide many values and services. The future of these forests will depend on many factors, including wood products markets, urban growth and development, insects and diseases, and climate changes.

Ecohydrology focuses on the interactions and interrelationships between hydrological processes and the structure and function of vegetation (Breshears 2005, Rodriguez-Iturbe 2000). It builds on a long history of watershed science that quantified how changes in vegetation (e.g., through purposeful manipulation. succession, or natural disturbances) alters water and streamflow dynamics at catchment scales (Bosch and Hewlett 1982, Vose and others 2014). Recent papers have broadened the scope to include understanding soil moisture dynamics (D'Odorinco and others 2010, Emanuel and others 2010),...