Debris Management in Alberta Fuel Management Workshop October 2003

1. Debris Management in AlbertaFuel Management WorkshopOctober 2003 Greg Baxter Researcher, WFORGFERIC Western Division

2. Background • Debris management has been an issue since the 1890’s when the first tree was harvested(P. Murphy) “The Dominion Timber Regulations were amended in 1898 to include requirements for disposal of logging debris and to require timber operators to share the costs of forest protection”. • This problem has been studied a number of times – this being the most recent.

3. Past Work (examples) • Bennett, W.D. 1960. The reduction of forest fire hazard created by logging slash. Literature review • Kiil, A.D. 1964 – moisture content of slash fuels. Also moisture content study five years after logging (1968) • 1972 Task Force report for the reduction of slash hazard on logging operations (Benson, J.E) (Hazard rating system and ‘wildfires from slash have not caused us any problems to date’.

4. Past Work • Little quantitative data collected on fire behaviour (intensities and spread mechanisms) of debris and piles involved in wildfires.

5. Current Issues • Provincial legislation states that slash hazard reduction is required – within 24 months (primarily by burning). • Some Companies would rather spread debris or pile and not burn – mostly due to liability concerns. • Are there alternatives? • Can we learn from the fire history or case studies of fire behaviour? Are there species differences?

6. Recent High Profile Fires Involving Debris • 1998 Slave Lake Fires • 2000 Cherry Hill Fire • 2001 Chisholm Fire • 2002 House River Fire • 2003 Lost Creek Fire

7. Observed Problematic Fire Behaviour • Spotting (pile-to-pile and pile to forest). • Pile-to-pile spread (radiation or direct flame contact). • Grass fire behaviour combined with heavy fuel loads. • Overnight fire spread. • Difficult/expensive to extinguish.

8. History of Debris Fires • Debris fires extracted from fire history database for the period 1961- 2000. Sorted by size, month, cost, cause and location. • Since 1961, debris has been involved in more than 3,200 fires as a primary or secondary fuel. • Lightning and land clearing activities are major sources of ignition.

9. Total Wildland Fires by Time Period

10. Debris Fires by Time Period

11. Debris fires 1961-2000 • Province wide distribution • West-central weighting • 3224 fires (~80/year or 10% of all fires)

12. Fires by Month

13. Ignition Two primary causes: • Lightning (~36%) June-August. • Land clearing: including forestry, transportation and private landowners. (~30%) (May-June). Other causes include: man accident (13%), equipment (5%) and vandalism (4%).

14. Lightning Fires (34%) • Province wide distribution with a grouping in the west-central region, the lightning belt in province. • 1134 fires

15. Industry Fires Includes: • Oil and Gas • Forestry • Other Industry • Transportation • 675 fires

16. Winter Fires Almost all burning occurs during winter; even with snow these can be problematic: • Wind events can cause winter burns to escape. There are many examples of Chinooks causing escapes resulting in fires of significant costs. • Holdover fires. Fires burned during winter and believed out, can re-surface and escape in the spring. This problem appears to be increasing.

17. Over-wintering firesFires ignited during winter that re-surface after April 1st.

18. Regional TrendsandRegional Solutions. The fire history revealed the number number of fires, causes and stand types vary in the province. Four regions stand out: • SE Slopes – Chinooks, steep slopes • East-central – aspen debris • West-central – lightning frequency • North – organic soils, lightning.

19. Regions • SE Slopes • East-central • West-central • North

20. Southeast Slopes • Abundant debris from decadent stands, steep slopes. • Fewer debris fires than other regions – but large, intense, expensive fires have recently occurred. • Winter burning is a concern – unreliable snowpacks and strong, unpredictable winds create problematic conditions. • Better knowledge of Chinooks required.

21. Southeast SlopesPotential Treatments • Must burn debris – problematic in wildfires. • 1 in 4 piles can be left as wildlife piles (based on fire history). • Development of an east-slope scale ‘Chinook Risk’ map. • Use of ‘Simple’ burn plans.

22. East-central Region • Characterized by large stand replacing fires. • Aspen is a harvested species. • Little research of fire behaviour in aspen debris. • Aspen piles have recently contributed to problematic fire behaviour.

23. East-central RegionPotential Treatments • Increase distance between aspen piles. Size limits to the piles. • Eliminate all coniferous debris. • Spreading aspen debris may be a potential solution. • Debris-free distance around values-at-risk (using WTA).

24. West-central Region Significantly more fires than any other regions: Why? • Region lies in THE lightning belt. • Heavy industry use over along time period. • Influenced by Chinook in western portion. • Increase in over-winter fires

25. West-central RegionPotential Solutions • Lightning location study. • Lightning mitigation techniques (are there any?). • One pile/4 hectares for wildlife piles. • Development of infrared scanning standards (includes equipment).

26. Northern Region • Aspen also harvested. • Highest percentage of lightning caused debris fires. • Generally stable winter burning conditions (few over-winter fires). • Ground fires are a concern.

27. Northern RegionSolutions • Soils map. • Aspen wildlife piles. • Lightning mitigation techniques. • Pile burn ‘checklist’ for industry and land-owners. • Combine FWI & snow-on-ground data to develop a ‘risk’ chart for burning.

28. Existing Fire Behaviour Research(available on web) Some research has occurred in the following areas: • Pile shape • Debris loading hazards - quantity • Debris age and hazard – needle retention • Moisture Content studies (age) • Aspen fire behaviour (limited) • Spotting models

29. Knowledge Gaps • Document fire behaviour in both conifer and aspen debris using case studies and ‘experimental’ debris fires. • Determine a scientifically based pile-to-pile distance to mitigate influence of debris piles during wildfires that includes: • Spread via spotting • Spread from radiation • Spread by direct contact

30. Knowledge Gaps (con’d) Debris Arrangement: Are there debris arrangements that may decrease fire intensity? I.e., • Spreading • Pile size and shape • Spatial distribution • Species specific guidelines

31. Mechanised Solutions • Slash bundler - cogen • Chipping • Mulching – “The Bull” May be used in targeted areas, but at this time uneconomic to treat all blocks.