Jeremy S. Fried

The wildland-urban interface in the United States

The wildland-urban interface (WUI) is the area where houses meet or intermingle with undeveloped wildland vegetation. The WUI is thus a focal area for human-environment conflicts, such as the destruction of homes by wildfires, habitat fragmentation, introduction of exotic species, and biodiversity decline. Our goal was to conduct a spatially detailed assessment of the WUI across the United States to provide a framework for scientific inquiries into housing growth effects on the environment and to inform both national policymakers and local land managers about the WUI and associated issues. The WUI in the conterminous United States covers 719 156 km? (9% of land area) and contains 44.8 million housing units (39% of all houses). WUI areas are particularly widespread in the eastern United States, reaching a maximum of 72% of land area in Connecticut. California has the highest number of WUI housing units (5.1 million). The extent of the WUI highlights the need for ecological principles in land-use planning as well as sprawl-limiting policies to adequately address both wildfire threats and conservation problems.

Homeowner Perspectives on Fire Hazard, Responsibility, and Management Strategies at the Wildland-Urban Interface

Following a survey of forest homeowners in rural Michigan to assess the value of reducing the risk of damage from wildfires at the wildland-urban interface, focus group discussions were conducted with a subset of survey participants to learn about their perceptions concerning specific components of fire hazard (e.g., how fires start, fire control, fire damage), their understanding of how fire protection responsibility is allocated between government and individuals, and their under standing of and preferences for alternative fire management strategies. Focus-group data were analyzed using a framework based on behavioral economics and psychometric models of risk. Attributes associated with the fire risk help explain the relative popularity of different fire protection strategies. Because participants consider forest fires inherently uncontrollable, and the resulting damage essentially random, they are only weakly supportive of investments in firefighting infrastructure, unlikely to take all possible steps ...Following a survey of forest homeowners in rural Michigan to assess the value of reducing the risk of damage from wildfires at the wildland-urban interface, focus group discussions were conducted with a subset of survey participants to learn about their perceptions concerning specific components of fire hazard (e.g., how fires start, fire control, fire damage), their understanding of how fire protection responsibility is allocated between government and individuals, and their under standing of and preferences for alternative fire management strategies. Focus-group data were analyzed using a framework based on behavioral economics and psychometric models of risk. Attributes associated with the fire risk help explain the relative popularity of different fire protection strategies. Because participants consider forest fires inherently uncontrollable, and the resulting damage essentially random, they are only weakly supportive of investments in firefighting infrastructure, unlikely to take all possible steps to safeguard their own properties, and resolute in their emphasis on solutions that reduce the number of fire ignitions. Their universally negative perceptions of prescribed fire may ultimately preclude its use as a risk management tool in Michigans wildland-urban interface forests.

Wildland-urban interface housing growth during the 1990s in California, Oregon, and Washington

In the present study, we examine housing growth in California, Oregon, and Washington in the wildland-urban interface (WUI), the area where homes and other structures abut or intermingle with wildland vegetation. We combine housing density information from the 1990 and 2000 USA censuses with land cover information from the 1992/93 National Land Cover Dataset to demarcate the location and extent of the WUI and its growth, both in terms of area and number of housing units during the 1990s. We overlay the WUI with coarse-scale fire regime condition class information to evaluate implications for wildland fire management. During the 1990s, WUI area in the three-state region increased by 5218 km 2 (10.9%) to nearly 53 000 km 2 and the number of housing units in the WUI increased over 1 million units (17.6%) and in 2000 encompassed 6.9 million units, 43% of all housing in the region. Over a million new homes were constructed in the WUI, comprising 61% of the new homes constructed in the region. By 2000, there was far more intermix WUI (75% of the WUI area and 64% of the WUI housing units) than interface WUI. Expansion of the WUI accounted for only 13% of WUI housing unit growth and WUI that existed in 1990 encompassed 98% of WUI housing units in 2000. In 2000, there were nearly 1.5 million WUI housing units in areas with 0-35-year fire return intervals and 3.4 million in areas with 35-100+ year fire return intervals. In both these fire regimes, the majority of WUI housing units (66% and 90% respectively) are in areas with a current condition outside the historic range of variability. Housing growth patterns in this three-state region are exacerbating wildland fire problems in the WUI. Any long-term solution to wildland fire issues in the western United States will have to address housing growth patterns. Using a consistent, nationally applicable assessment protocol, the present study reveals the vast extent of WUI in the west coast states and its growth in the 1990s, and provides a foundation for consistent monitoring efforts.

Predicting the impacts of global warming on wildland fire

Simulations of impacts of a double-CO2 climate with the Changed Climate Fire Modeling System in Northern California consistently projected increases in area burned and in the frequency of escaped fires compared with simulations of the present climate. However, the magnitude of those increases was strongly influenced by vegetation type, choice of atmospheric general circulation model (GCM) scenario, and choice of climatic forcing variables. The greatest projected increase in fire severity occurred in grasslands, using the Princeton Geophysical Fluid Dynamics Laboratory GCM, with wind speed, temperature, humidity and precipitation as driving variables.

Predicting Homeowners' Approval of Fuel Management at the Wildland–Urban Interface Using the Theory of Reasoned Action

ABSTRACT Social science models are increasingly needed as a framework for explaining and predicting how members of the public respond to the natural environment and their communities. The theory of reasoned action is widely used in human dimensions research on natural resource problems and work is ongoing to increase the predictive power of models based on this theory. This study examined beliefs, attitudes, and intention to support the implementation of three fuel management approaches (FMA)—prescribed burning, mechanical fuel reduction, and defensible space ordinances—in three wildland–urban interface (WUI) areas in the United States. Besides factors prescribed by the theory, the influence of three additional explanatory variables was assessed: past experience, personal importance, and trust. Personal importance of a FMA was a consistently significant predictor of attitude toward that approach, and trust in an agencys implementation of that approach was also a predictor of intention to approve the use of that approach.

Mapping wildland fuels and forest structure for land management: a comparison of nearest neighbor imputation and other methods

Land managers need consistent information about the geographic distribution of wildland fuels and forest struc- ture over large areas to evaluate fire risk and plan fuel treatments. We compared spatial predictions for 12 fuel and forest structure variables across three regions in the western United States using gradient nearest neighbor (GNN) imputation, lin- ear models (LMs), classification and regression trees (CART), and geostatistical methods (kriging and universal kriging (UK)). Local-scale map accuracy varied considerably across sites, variables, and methods. GNN performed best for forest structure variables in Oregon, but LMs and UK were better for canopy variables and for forest structure variables in Wash- ington and California. Kriging performed poorly throughout, and kriging did not improve prediction accuracy when added to LMs as UK. GNN outperformed CART in predicting vegetation classes and fuel models, complex variables defined by multiple attributes. Regional distributions of vegetation classes and fuel models were accurately represented by GNN and very poorly by CART and LMs. Despite their often limited accuracy at the local scale, GNN maps are useful when infor- mation on a wide range of forest attributes is needed for analysis and forest management at intermediate, i.e., landscape to ecoregional, scales.

Deploying wildland fire suppression resources with a scenario-based standard response model

Wildland fire managers deploy suppression resources to bases and dispatch them to fires to maximize the percentage of fires that are successfully contained before unacceptable costs and losses occur. Deployment is made with budget constraints and uncertainty about the daily number, location, and intensity of fires, all of which affect initial-attack success. To address the deployment problem, we formulate a scenario-based standard response model with two objective functions: the number of suppression resources deployed and the expected daily number of fires that do not receive a standard response, defined as the desired number of resources that can reach the fire within a specified response time. To determine how deployment levels affect the standard response objective, a weighted sum of the objective functions is minimized, and the weights are ramped from large to small to generate the tradeoffs. We use the model to position up to 22 engines among 15 stations in the Amador-El Dorado unit of the California Department of Forestry and Fire Protection in central California. Each deployment is further evaluated in terms of expected number of escaped fires using CFES2, a stochastic simulation model of initial attack. The solutions of the standard response model form a tradeoff curve where increasing numbers of engines deployed reduces the expected daily number of fires not receiving the standard response. Solutions concentrate engines in a small set of centrally-located stations. We use a simple heuristic with CFES2 to incrementally remove engines based on simulation estimates of expected utilization frequency. The deployments obtained with the heuristic contain about the same number of fires as do solutions of the standard response model, but the heuristic solutions deploy engines to more stations.

Hardwood Rangeland Landowners in California from 1985 to 2004: Production, Ecosystem Services, and Permanence

Abstract A longitudinal study of California hardwood rangelands shows significant change in landowner characteristics and goals. Results of three studies spanning 1985 to 2004 were used to develop and evaluate a multiagency research and extension program known as the Integrated Hardwood Range Management Program. Program-sponsored education and research aimed at encouraging landowners to change woodland management has been reflected in a significant reduction in oak cutting and an increase in oak planting. Recent changes have come with the times: landowners were as likely to have consulted land trusts about oaks as Cooperative Extension, and the number engaged in production of crops or livestock continued to decline. On the other hand, the proportion of landowners, including ranchers, reporting that they live in the oak woodland to benefit from ecosystem services such as natural beauty, recreation, and lifestyle benefits significantly increased. Though owners of large properties and ranchers were more strongly against regulation and “government interference” than other respondents, this did not appear to affect oak values and management. Property size remained significantly related to landowner goals, values, and practices, with those producing livestock owning most of the larger properties. There has been a decline in the number of properties being studied due to conversion of some from oak woodland to other uses, though the remaining respondents still own at least 10% of the woodlands. Landowners with conservation easements or those who are willing to consider them, who believe oak recruitment is inadequate, or who use advisory services were significantly less likely to cut oaks and more likely to plant them. Policy, management, and outreach that support synergies between production and conservation activities, and that combine ecosystem service-based income streams that encourage keeping land intact and increased land-use stability, are needed to support conservation of private rangelands.

Analysing initial attack on wildland fires using stochastic simulation

Stochastic simulation models of initial attack on wildland fire can be designed to reflect the complexity of the environmental, administrative, and institutional context in which wildland fire protection agencies operate, but such complexity may come at the cost of a considerable investment in data acquisition and management. This cost may be well justified when it allows for analysis of a wider spectrum of operational problems in wildland fire protection planning. The California Fire Economics Simulator version 2 (CFES2), is a sophisticated stochastic simulation model designed to facilitate quantitative analysis of the potential effects of changes in many key components of most wildland fire systems, e.g. availability and stationing of resources, dispatch rules, criteria for setting fire dispatch level, staff schedules, and deployment and line-building tactics. The CFES2 model can also be used to support strategic planning with respect to vegetation management programs, development at the wildland–urban interface, reallocation of responsibilities among fire protection agencies, and climatic change. The analytical capacity of stochastic simulations models to address such key issues is demonstrated using the CFES2 model in four case studies addressing the impact on initial attack effectiveness of: (1) multiple fire starts; (2) diversion of firefighting resources to structure protection; (3) alternate stationing of firefighting resources; and (4) multi-agency cooperation.

Estimates of live-tree carbon stores in the Pacific Northwest are sensitive to model selection

BackgroundEstimates of live-tree carbon stores are influenced by numerous uncertainties. One of them is model-selection uncertainty: one has to choose among multiple empirical equations and conversion factors that can be plausibly justified as locally applicable to calculate the carbon store from inventory measurements such as tree height and diameter at breast height (DBH). Here we quantify the model-selection uncertainty for the five most numerous tree species in six counties of northwest Oregon, USA.ResultsThe results of our study demonstrate that model-selection error may introduce 20 to 40% uncertainty into a live-tree carbon estimate, possibly making this form of error the largest source of uncertainty in estimation of live-tree carbon stores. The effect of model selection could be even greater if models are applied beyond the height and DBH ranges for which they were developed.ConclusionsModel-selection uncertainty is potentially large enough that it could limit the ability to track forest carbon with the precision and accuracy required by carbon accounting protocols. Without local validation based on detailed measurements of usually destructively sampled trees, it is very difficult to choose the best model when there are several available. Our analysis suggests that considering tree form in equation selection may better match trees to existing equations and that substantial gaps exist, in terms of both species and diameter ranges, that are ripe for new model-building effort.