We designed and developed an internet mapping application to collect data on the locations of forest landscape values across a 2.4 million hectare study area in the province of Alberta, Canada. Four communities in the study area were surveyed and 8053 point locations were mapped for 10 different value types. Importance weights of landscape values were determined through a ranking exercise. Nearest-neighbour and second-order spatial point pattern analysis (K functions) suggested that all value types were significantly clustered across the study area. Recreational, wilderness, existence, and biological diversity values exhibited maximum clustering at larger spatial scales in comparison with educational, economic, historic or cultural, and spiritual values. Maximum clustering was positively related to mean road density and negatively related to mean distance to water, which suggests that landscape features influence the spatial pattern of values by acting as focal points or attractors for values. An applied use of the data for values hotspot detection and community protection zoning in forest fire management planning is presented.

We investigated the likelihood that short-duration sustained flaming would develop in forest ground fuels that had direct contact with a small and short-lived flame source. Data from 1027 small-scale experimental test fires conducted in field trials at six sites in British Columbia and the North-West Territories between 1958 and 1961 were used to develop logistic regression models for ten fuel categories that represent unique combinations of forest cover, ground fuel type, and in some cases, season. Separate models were developed using two subsets of independent variables: (1) weather variables and fuel moisture measurements taken at the site of the test fire; and (2) Canadian Fire Weather Index (FWI) system components calculated from weather observations recorded at a nearby station. Results indicated that models developed with FWI system components were as effective as models developed with site variables at predicting the probability of short-duration sustained flaming in most fuel categories. FWI system components were not useful for predicting sustained flaming in spring grass fuels and had limited usefulness for modelling the probability of sustained flaming in aspen leaf ground fuels during summer conditions. For all other fuel categories, FWI system components were highly effective substitutes for site variables for modelling the probability of sustained flaming.

We assessed the exposure of the built environment to potential ignition sources generated from vegetative fuel for four communities in the province of Alberta, Canada. Ignition processes generated by burning vegetation that were included in the analysis were radiant heat, short-range spotting, and longer-range spotting. Results were used to map the boundaries of the wildland–urban interface and to delineate zones within each community that identify the degree to which these areas represent potential wildfire entry-points into the wildland–urban interface. The assessment method can be used to set priorities for mitigation activities; compare conditions within and between communities and over time; and identify priority areas for time- and resource-intensive site assessments that are often completed for individual structures located in the wildland–urban interface. We compared results among the four case-study communities and demonstrated an application of the approach for evaluating community fuel treatment plans. Factors that influenced the exposure of the built environment to potential ignition sources differed among the communities, which suggested the need for community-specific mitigation strategies. Spatial patterns of areas with elevated ignition exposure reflected not only the amount of ignition-producing vegetation around the built environment, but also the size and arrangement of fuel patches in relation to the unique morphology of the community and the occurrence of occluded interface zones.

Stand-level fuel reduction treatments in the Canadian boreal zone are used predominantly in community protection settings to alter the natural structure of dominant boreal conifer stands such as black spruce (Picea mariana (Mill.) BSP), jack pine (Pinus banksiana Lamb.) and lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia). The aim of these fuel treatments is to inhibit the development of fast-spreading, high-intensity crown fires that naturally occur in boreal forest ecosystems. We document fuel treatment design standards used in boreal forests in Canada and review data requirements and methodological approaches for investigating fuel treatment effects on fire behaviour. Through a series of illustrative examples and summaries of empirical observations, we explore the implications of data and modelling assumptions used to estimate fire behaviour in fuel-treated areas and identify insights about fuel treatment effectiveness in boreal conifer stands. Fuel treatments in black spruce, jack pine and lodgepole pine stands were generally effective at reducing modelled and observed fire behaviour and inhibiting crown fire development and spread under low to moderate fire weather conditions. Evidence suggests that fuel treatments in these fuel types will be ineffective when rates of spread and wind speeds are very high or extreme. High surface fuel loads combined with the relatively short stature of boreal conifer trees can further undermine fuel treatment efforts. Priority areas for future study include examining alternatives for managing surface fuel loads in treated stands, exploring the viability of alternative horizontal fuel reduction protocols such as clumped fuel configurations, and integrating suppression and containment strategies within the fuel treatment planning and design process.

In black spruce forests characterised by high-intensity crown fires, early detection and containment of fires while they are small is crucial for averting progression to fire intensities that exceed suppression capabilities. Fire behaviour conditions encountered during initial attack operations are a key determinant of containment success. Conditions will be controlled in part by stand structural characteristics that can be expected to vary as a fire-origin black spruce (Picea mariana (Mill.) B.S.P.) stand ages with increasing time-since-fire. In this study, the influence of time-since-fire on containment outcomes is assessed to explore whether or not prior wildfire exerts a negative feedback on subsequent fires in these ecosystems. Logistic regression analysis using point and polygon fire data for the province of Alberta, Canada, indicated the probability of a containment failure in black spruce increases with time-elapsed since the last fire. Other positive explanatory variables included the size of the fire at the initiation of firefighting and a relative rating of the expected rate of fire spread, the Initial Spread Index (ISI) of the Canadian Forest Fire Weather Index System. Legacy wildfires had a protective effect. When firefighting is initiated at fire sizes ≤1 ha, the probability of a containment failure is low during the initial 20–45 years of post-fire stand development, except under the most extreme fire weather conditions.