Treesearch

As climatic conditions shift in coming decades, persistence of many populations will depend on their ability to colonize habitat newly suitable for their climatic requirements. Opportunities for such range shifts may be limited unless areas that facilitate dispersal under climate change are identified and protected from land uses that impede movement. While many climate adaptation strategies focus on identifying refugia, this study is the first to characterize areas which merit protection for their role in promoting climate connectivity at a continental extent. We identified climate...

Scarlet globemallow is the most widely distributed globemallow species (Sphaeralcea) in North America (Pendery and Rumbaugh 1993). It occurs from British Columbia to Manitoba and south to Arizona, New Mexico, Texas, and Chihuahua, Mexico (La Duke 2016). It is more common in the Great Plains than in the Intermountain region (Pendery and Rumbaugh 1993). Variety coccinea is found throughout the species range but elata occurs only in New Mexico, Texas, and northern Mexico (La Duke 2016).

Breeding programs are an important tool for managing invasive insects and diseases causing high mortality rates and even threatening extinction of some of our forest tree species. The emerald ash borer (EAB) invasion of North America, as one example, has resulted in five North American ash species being listed as "critically endangered" on the IUCN red list (IUCNredlist.org). Impacts from such significant losses are far-reaching. Wildlife species that depend on threatened tree species can also be at risk of extinction, Mortality of riparian tree species such as Eastern hemlock, currently...

There is enormous interest in applying connectivity modelling to resistance surfaces for identifying corridors for conservation action. However, the multiple analytical approaches used to estimate resistance surfaces and predict connectivity across resistance surfaces have not been rigorously compared, and it is unclear what methods provide the best inferences about population connectivity. Using a large empirical data set on puma (Puma concolor), we are the first to compare several of the most common approaches for estimating resistance and modelling connectivity and validate them with...

In Phase III of the North American Forest Dynamics (NAFD) study an automatic workflow has been developed for evaluating forest disturbance history using Landsat observations. It has four major components: an automated approach for image selection and preprocessing, the vegetation change tracker (VCT) forest disturbance analysis, post-processing, and validation. This approach has been applied to the conterminous US (CONUS) to produce a comprehensive analysis of US forest disturbance history using the NASA Earth Exchange (NEX) cloud computing system. The resultant NAFD-NEX product includes...

Recent studies of the Forest Service’s National Visitor Use Monitoring data show a wide disparity in racial and ethnic use of national forests. For example (assuming a direct connection between the number of people who filled out forms and overall national forest visitation numbers), Blacks or African Americans, who make up about 13 percent of the U.S. population, accounted for about 1 percent of national forest visits in 2010. Hispanics or Latinos, who make up about 17 percent of the U.S. population, accounted for less than 7 percent. Researchers at the Rocky Mountain Research Station in...

Restoration of longleaf pine (LLP) is a prominent land management objective throughout the Southeastern United States. Several recent tree- and plot-scale studies suggest that water yield from LLP-dominated landscapes may increase relative to loblolly or mixed pine hardwoods due to differences in stand structure and the higher water use efficiency of LLP. Here we present a new long-term, watershed scale study to test those hypotheses, whereby a watershed dominated by loblolly pine is being restored to LLP using operational silvicultural treatments. We are using a paired watershed approach...

The boreal biome represents approximately one third of the world’s forested area and plays an important role in global biogeochemical and energy cycles. Numerous studies in boreal Alaska have concluded that growth of black and white spruce is declining as a result of temperature-induced drought stress. The combined evidence of declining spruce growth and changes in the fire regime that favor establishment of deciduous tree species has led some investigators to suggest the region may be transitioning from dominance by spruce to dominance by deciduous forests and/or grasslands. Although...

The determination of invasion stages and the degree to which an invasive plant (non-native invasive plant, NNIP) has become established and spread in an ecosystem (\invasiveness") is essential for developing methods of mitigation and control. We mapped the invasion stages and quantified the invasiveness of four NNIPs of great concern, multiflora rose (Rosa multiflora Thunb), nonnative bush honeysuckles (including four species from the Lonicera spp family), common buckthorn (Rhamnus cathartica L.) and garlic mustard (Alliaria petiolata [M. Bieb.] Cavara & Grande) in the Upper Midwest...

Wood decay fungi are any species of fungi that utilise the structural components of wood as a source of nutrients. They comprise a very diverse group and have a worldwide distribution normally wherever trees are found. Wood decay fungi are vital to ecosystem functioning as they facilitate the decomposition of woody materials into soil. Wood decay fungi are also major contributors to damage to wood in service in both residential and industrial applications, leading to estimated $1B in losses annually. Wood decay fungi have also been exploited for use in industrial processes ranging from...