Treesearch

Yellow birch (Betula alleghaniensis Britton) is a small-seeded hardwood tree native to forests across northeastern North America. Genetic diversity of this species is high due to high levels of seed dispersal and pollen flow, though few parameters that describe gene flow have been reported. Yellow birch is capable of hybridizing with other Betula species. Common garden studies revealed relatively weak clines for growth traits but strong variation in phenological traits, indicating that seed transfer may be deleterious if seed is moved long distances. No empirical transfer distances have...

Accurately predicting pedestrian travel times is critically valuable in emergency response, wildland firefighting, disaster management, law enforcement, and urban planning. However, the relationship between pedestrian movement and landscape conditions is highly variable between individuals, making it difficult to estimate how long it will take broad populations to get from one location to another on foot. Although functions exist for predicting travel rates, they typically oversimplify the inherent variability of pedestrian travel by assuming the effects of landscapes on movement are...

Whitebark pine (Pinus albicaulis Engelm.) is an ecologically important subalpine and treeline forest tree of the western U.S. and Canada. It is categorized as endangered by the IUCN and by Canada under the Species at Risk Act and was recently proposed for listing in the U.S. as threatened under the Endangered Species Act. Whitebark pine populations are declining nearly rangewide primarily from the spread and intensification of Cronartium ribicola J.C. Fisch., the exotic, invasive pathogen that causes white pine blister rust (WPBR); recent, large-scale outbreaks of mountain pine beetles...

Westslope Cutthroat Trout Oncorhynchus clarkii lewisi (WCT), the dominant nonanadromous salmonid in central and northern Idaho, historically were extremely abundant and widely distributed. Despite restricted harvest methods and limits since 1899, many WCT populations declined and by the 1960s, populations in several major drainages were on the brink of collapse. In response, fisheries biologists began investigating WCT population dynamics, life histories, and habitat requirements and developed evidence-based regulations and habitat restoration alternatives. Here we describe fluvial WCT...

Restoring wide areas of fire excluded western US landscapes to fuel limited, fire resilient systems where fires self-regulate and burn with low or mixed severity will require expanded use of both prescribed and natural fire, coupled with strategic mechanical fuels management. However, optimal admixtures of fire and fuel management to set landscapes on trajectories to improve fire resilience and conserve carbon are not well understood.

The National Predictive Services (NPS) asked the USFS Rocky Mountain Center for Fire-Weather Intelligence (RMC) as a part of the Fire, Fuel, and Smoke Science Program (FFS) at the USFS Rocky Mountain Research Station (RMRS) to assist with the development of a system of statistical models for predicting the ignition probability (chance of start) & growth potential of wildfires on a national grid using NWS meteorological forecast data as input. The development of this gridded system of predictive equations was envisioned to proceed in 3 stages (phases).

Sapwood comprises much above-ground forest biomass, but its mycobiome in living trees is largely unknown. Here, we characterize the endophytic fungal communities of the functional sapwood of young and mature living beech trees (Fagus sylvatica) at multiple scales, from within individual trees to woodland sites across the southern United Kingdom. Fungal community composition was determined using both culture-based and molecular approaches across two loci. Wood decay fungi, including those that cause heart rot, were detected in approximately 80% of all samples. Fungal community composition...

The biogeochemical model, PnET-BGC, was modified and parameterized using field data from an experimental whole-tree harvest of watershed (W5) in 1983–1984 at the Hubbard Brook Experimental Forest (HBEF), New Hampshire, USA. The model simulated the hydrology, biomass accumulation, and soil solution and stream water chemistry responses to forest cutting. The parameterized model was then applied to other experimentally cut watersheds at the HBEF; including a devegetation experiment (W2; devegetation and herbicide treatment) and a commercial strip-cut (W4) to evaluate the ability of the model...

Forest and freshwater ecosystems are tightly linked and together provide important ecosystem services, but climate change is affecting their species composition, structure, and function. Research at nine US Long Term Ecological Research sites reveals complex interactions and cascading effects of climate change, some of which feed back into the climate system. Air temperature has increased at all sites, and those in the Northeast have become wetter, whereas sites in the Northwest and Alaska have become slightly drier. These changes have altered streamflow and affected ecosystem processes,...

Fire has transformative effects on soil biological, chemical, and physical properties in terrestrial ecosystems around the world. While methods for estimating fire characteristics and associated effects aboveground have progressed in recent decades, there remain major challenges in characterizing soil heating and associated effects belowground. Overcoming these challenges is crucial for understanding how fire influences soil carbon storage, biogeochemical cycling, and ecosystem recovery. In this paper, we present a novel framework for characterizing belowground heating and effects. The...