Global climate change has the potential to affect future wildfire activity, particularly in south-western USA ponderosa pine forests that have been substantially altered by land-use practices and aggressive fire suppression.

Mechanical mastication is increasingly used as a wildland fuel treatment, reducing standing trees and shrubs to compacted fuelbeds of fractured woody fuels. One major shortcoming in our understanding of these fuelbeds is how particle fracturing influences moisture gain or loss, a primary determinant of fire behaviour.

Reducing stand density is often used as a tool for mitigating the risk of high-intensity crown fires. However, concern has been expressed that opening stands might lead to greater drying of surface fuels, contributing to increased fire risk. The objective of this study was to determine whether woody fuel moisture differed between unthinned and thinned mixed-conifer stands.

Though the need for prescribed fire is widely recognised, its use remains subject to a range of operational and social constraints. Research has focussed on identifying these constraints, yet past efforts have focussed disproportionately on single agencies and geographic regions.

This study evaluates the consumption of coarse woody debris in various states of decay. Samples from a northern Idaho mixed-conifer forest were classified using three different classification methods, ignited with two different ignition methods and consumption was recorded.

The impacts of climatic changes on forests may appear gradually on time scales of years to centuries due to the long generation times of trees. Consequently, current forest extent may not reflect current climatic patterns.

Highlights • Wildfire may exacerbate health disparities & environmental justice concerns. • Low-cost PM2.5 sensors improve wildfire impact assessment. • Increases in PM2.5 correlate with wildfire activity (within 30 km). • Indoor increases in PM2.5 concentrations mimic outdoor PM2.5 increase patterns.

Losses of C and N from the forest floor and top 20-cmof soil were estimated following separate severe wildfires at two Long-Term Soil Productivity sites in the Sierra Nevada of California, USA.

Throughout North America, rapid exurban development is increasing the spatial extent and population density of the wildland urban interface (WUI), exacerbating problems of wildfire risk and biodiversity loss. To address these issues, policy and planning tools need to be targeted toward different types of WUI landowners in the different types of landscape locations they occupy.

Existing research demonstrates that wildfire events can lead to conflict among local residents and outside professionals involved in wildfire management or suppression.