Timber harvest companies are looking for cost-effective methods for harvesting low value fibre. FPInnovations conducted a multi-faceted research project in the Nazko region to compare several operational aspects of two harvest methods: cut-to-length and conventional.
As part of this research project, FPInnovations’ wildfire group measured and assessed the harvest residue resulting from both harvest methods. With this information, we were able to evaluate potential fire behaviour in each of the harvest areas.
Evaluation of forest environments to assess fuel loading using conventional inventory methods is labour-intensive, time-consuming, and requires extensive training to be completed correctly. Fuels managers would like to apply simpler, less expensive fuel sampling methods and still maintain acceptable accuracy in fuel load measurements.
FPInnovations has explored different fuel sampling techniques that may be applicable to the forest stands of central British Columbia. The photoload sampling technique was deemed to be a valuable tool that can be enhanced to suitably represent the forest fuels in Interior Douglas-fir environments and can be adapted to other fuel environments with appropriate amendments.
The City of Quesnel, B.C. has applied an innovative selective harvesting technique in a mature Douglas-fir forest stand with the objectives of maintaining biodiversity and reducing fuel-load buildup and consequent wildfire threat. FPInnovations researchers monitored and documented the harvesting operations and measured machine productivity to evaluate the cost-effectiveness of the operation.
To support the assessment of fuel-load reduction, FPInnovations’ Wildfire Operations group conducted pre- and post-harvest fuel-sampling activities to evaluate changes in forest fuel components.
Oriented residue piles and constructed burn piles have different characteristics, including fuel size, composition, and fuel arrangement. The comparative ignition trials conducted in this proof-of-concept study suggest that these characteristics influence the fuel environment, with a higher potential for ignition and sustained burning and greater resultant fire intensity in constructed burn piles. The intent of this proof-of-concept trial was to determine whether logging residue piles that have been oriented for biomass extraction (placed in parallel piles by the processor operator during primary harvesting activities) is a significant fuel hazard that requires further abatement.
Forest fuels engineering is one of the primary wildfire mitigation strategies advocated by FireSmart™ Canada and applied by partnering wildfire management agencies and industry operators. Fuel treatments have been extensively applied in and around communities in the wildland-urban interface, through a broad range of fuel modification techniques. A primary objective of fuel treatments is to modify fire behaviour to a ‘less difficult, disruptive, and destructive’ state (Reinhardt et al. 2008) which can allow for safer, more effective fire suppression operations (Moghaddas and Craggs 2007).
Black spruce is one of the most prevalent fuel types surrounding communities in central and northern Alberta, as well as other parts of boreal Canada. The densely stocked black spruce forest stands in the Red Earth Creek FireSmart research area exhibit typical crown fuel properties of black spruce: high crown bulk density and low crown base height, which contribute to crown fire initiation (Van Wagner 1977). These fuel characteristics, combined with low fuel moisture contents and strong winds, create ideal conditions for high-intensity, rapidly-spreading catastrophic wildfire (Flat Top Complex Wildfire Review Committee 2012).
Mulch fuel treatments use various types of equipment to masticate forest vegetation resulting in a reduction in crown bulk density and the conversion of canopy and ladder fuels to a more compacted and less available fuel source in the surface layer (Battaglia et al. 2010). Mulch thinning and strip mulch treatments create a more open surface fuel environment with both negative and positive impacts. Due to increased exposure to sun and wind flow, the chipped debris and other surface fuels in the open areas of the treatments dry more quickly than fine fuels in enclosed stands (Schiks and Wotton 2015). From a control perspective, the open thinned areas of the treatments allow more effective penetration of water/suppressant through canopy fuels to surface fuels (Hsieh in progress). Additionally, fine fuels at the surface of openings respond more quickly to water and suppressant application. Open areas of the treatments that have been wetted by sprinkler systems or aerial water delivery should reduce the potential for ignition and sustained burning, providing a potential barrier to fire spread.
Experimental crown fires have been conducted to challenge fuels treatments in other forest fuel types (Schroeder 2010, Mooney 2013) to evaluate the efficacy of these treatments in moderating fire behaviour. Mechanical (shearblading) fuel treatments in black spruce fuels (Butler et al. 2013) have been shown to reduce fire intensity. However, documentation of crown fire challenging mulch fuel treatments in black spruce fuels is limited. Fire and fuels managers would like to evaluate the effectiveness of mulch fuel treatments in reducing fire intensity and rate of spread and, ultimately, their ability to mitigate wildfire risk to communities surrounding these hazardous fuels.
Alberta Agriculture and Forestry (AAF) Wildfire Management Branch fuels managers designed the Red Earth Creek FireSmart research area with the objective of conducting research that will lead to a better understanding of mulch fuel treatments and how these changes in the black spruce fuel environment affect fire behaviour. On May 14, 2015, Slave Lake Forest Area personnel conducted an experimental fire at this site; FPInnovations and research partners collected data to document changes in fire behaviour.
Forest fuels engineering is one of the primary wildfire mitigation strategies advocated by FireSmart™ Canada (Partners in Protection, 2003) and applied by partnering wildfire management agencies and industry operators. Over the past two decades, mechanical forest fuel treatments (including mulching) have been extensively applied in and around communities in the wildland-urban interface to mitigate the risk of wildfire. Fuel managers and fire operations managers would like to better understand how manual and mechanical fuel treatments modify fire behaviour.
Fuel treatment efficacy has been evaluated through post-wildfire case studies (Mooney, 2014; Pritchard et al., 2011), fire behaviour modelling (Fernandes, 2009; Stephens et al., 2009) and subjective expert opinion based approaches (Hayes et al., 2008). The use of experimental fire to evaluate the effectiveness of fuel treatments is limited.
The Canadian Boreal Community FireSmart project has been the site of several research projects designed to evaluate the efficacy of fuel treatments in mitigating wildfire. In June 2016, FPInnovations conducted an experimental crown fire which challenged a mulch fuel treatment.
FPInnovations collaborated with Alberta Agriculture and Forestry and other research agencies to conduct two experimental fires in mulched fuels under very high fire hazard conditions.
This study documented fire behaviour and compared it to other experimental fires in mulch fuel beds at other independent study sites. Documentation of fire behaviour in this novel fuel type can inform wildfire managers of potential fire behaviour and suppression challenges.
Firebrand transport is a key mechanism for fire spread. Fire and fuels managers apply fuel treatments in the wildland–urban interface based on our best understanding of firebrand transport and spot fire growth. Observations and data collected during this experimental fire can lend to innovations in firebrand transport data collection methods and fuel treatment maintenance practices.