Understory

Effective beginning 5/30/2025This website, and all linked websites under the control of the agency, is under review and content may change.A climate change vulnerability assessment, or CCVA, is a report that synthesizes and evaluates a wide range of scientific information, including model projections and scientific papers, on the effects climate change might have on a specific area. This fact sheet summarizes the main parts and uses of a CCVA, and highlights the role WWETAC plays in producing many of the assessments for the Western U.S. It also includes an up-to-date list of WWETAC's available...

Fiscal Year 2024 Executive SummaryWe had a productive fiscal year 2024, completing work on 15 field projects across 7 national forests and continuing support of Southern Research Station projects. We deployed our field teams to areas as far away as Arkansas, Florida, and Alabama while tackling projects from stream fish and habitat monitoring to outreach and education. We provided our partners with information and resources they need to maintain or restore healthy watersheds, prioritize infrastructure improvement projects, connect people to the outdoors, and deliver high quality science.Fiscal ...

Compiled abstracts of the 2024 National Silviculture Workshop, sponsored by the U.S. Forest Service, July 16-18, 2024, at the Greater Tacoma Convention Center in Tacoma, WA.

This photo sequence can be used to estimate masticated fuel loads with the Photoload technique.

This photo sequence can be used to estimate cone fuel loading with the Photoload technique.

In most cases, it is not feasible to count every element of a population. This limitation is particularly true in a forest inventory because tallying every tree is prohibitively expensive and time consuming. As such, sampling is used to estimate the population totals for attributes of interest (e.g., number of trees). Sample size, plot design, measurement procedures, and ecological modeling all impact the degree of uncertainty associated with the resulting estimates. It is critical to understand these influences and to consider the level of confidence in an estimate when using the data for dec...

Wildfires are increasing in size and severity, as well as in social, economic, and environmental costs. These wildfire events that once affected only rural and Wildland-Urban Interface (WUI) communities are now more frequently affecting cities and highly populated, densely built, and diverse communities throughout the world. These events are now being referred to as “urban fires” since they are no longer solely driven by vegetation fuel types and altered climates and landscape treatments, but also by flammable building structures, extreme wind events, and urban forest structure, composition, a...