Treesearch

Land managers rely on best available information and relevant research for decision making, but matching the right information to the right questions can sometimes be challenging. To close this gap, when researchers and managers co-produce research from the beginning it is more likely research findings will have practical applications. Recently published work by USDA Forest Service researchers Chris Armatas, Teresa Hollingsworth, and colleagues working at the Aldo Leopold Wilderness Research Institute (ALWRI) in Missoula, Montana, reflects on both the benefits and tradeoffs of using a...

Aspen (Populus tremuloides) forests are generally thought to impede fire spread, yet the extent of this effect is not well quantified in relation to other vegetation types. We examined the influence of aspen cover on interpolated daily fire spread rates, the relative abundance of aspen at fire perimeters versus burn interiors, and whether these relationships shifted under more fire-conducive atmospheric conditions. Our study incorporated 314 fires occurring between 2001 and 2020 in the southwestern United States and a suite of gridded vegetation, topography, and fire weather predictor...

In recent years, the U.S. Federal government has advanced shared stewardship (see Study Background for definition) of Federal lands with American Indian Tribes across land management agencies. Yet little is understood about how these efforts are carried out in the context of Wild and Scenic Rivers (WSRs). The WSRs are managed across four Federal land management agencies: the Bureau of Land Management, the Forest Service, the National Park Service, and the U.S. Fish and Wildlife Service. Rivers designated under the WSR Act are managed to protect their free-flowing, undammed quality, along...

Individual fire history studies paint a picture of how often and how severely fires burned on specific landscapes, providing valuable points of evidence for land management decisions. Syntheses of multiple fire history studies weave these individual pictures into a panoramic tapestry, providing a more complete understanding of historical fire regimes. For example, syntheses of fire history studies in ponderosa pine communities tell stories about precolonial historical fires frequently burning small areas and occasionally burning large areas, followed by a century with very few fires due to...

Healthy streams play a critical role in supporting plant, fish, and animal communities. However, stream degradation is a global problem that threatens the condition of these important ecosystems. Channel incision is one way that streams can change in response to natural or human processes. This process of degradation leads to lower water tables and a lost connection to the floodplain. As a result, water availability changes for the riparian plant communities, resulting in further degradation.

Tree age information is crucial for a range of environmental, scientific, and conservation-related purposes. It helps in understanding and managing forest resources effectively and sustainably. This study presents an approach to estimate tree age across diverse U.S. forested ecosystems using field inventory and climate datasets. The age-size relationship modeling framework incorporates species-specific and environmental variables, enabling its application across various regions. Model R² values range from 0.51 to 0.87 and relative RMSEs (using the mean as the denominator) ranging from 0.14...

The hierarchical model-based (HMB) statistical method is currently applied in connection withNASA’s Global Ecosystem Dynamics Investigation (GEDI) mission for assessing forest aboveground biomass (AGB) in areas lacking a sufficiently large number of GEDI footprints for employing hybrid inference. This study focuses on variance estimation using a bootstrap procedure that separates the computations into parts, thus considerably reducing the computational time required and making bootstrapping a viable option in this context. The procedure we propose uses a theoretical decomposition of the...

Background: Remote sensing techniques for assessing fire severity using two-dimensional imagery, such as satellite data, are limited to a single severity value per pixel, typically at a 30-m resolution. This often leads to an underestimation of understory fire severity, as live tree crowns can obscure the extent of the burned area beneath. By leveraging the three-dimensional capabilities of drone imagery, a more comprehensive assessment of fire severity across different canopy height strata can be achieved.Methods: We show how drone digital aerial photogrammetry (dDAP), also known as...

The mixed estimator (ME) for annual forest inventory proposed by van Deusen (1999; Can. J. For. Res. 29: 1824-1828) is reformulated as a linear mixed model. This equivalent structure admits an interpretation of the ME as a polynomial regression on year with correlated year-specific random effects. It also uncovers the necessary criterion for maximum likelihood (ML) estimation. The improved performance of the ME under ML estimation is illustrated through simulations and application to inventory data from Montana, USA. Limitations of the ME relating to model-misspecification are also discussed.

Homeowner wildfire risk mitigation and preparedness are critical components of community wildfire readiness. This report describes the data collected through two efforts conducted in the Estes Valley Fire Protection District of Larimer County, Colorado, study area: (1) parcel-level rapid wildfire risk assessments performed by trained assessors and (2) homeowner surveys in which respondents provided self-assessments of their parcel-level wildfire risk. This project was undertaken to support Estes Valley Fire Protection District’s desire to enhance resident wildfire risk mitigation and...