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This, . Or This. Fire Behavior Basics. Causes of Stand Replacement FiresTopographySlopeDrainages affecting wind patternsVegetation patternsWeatherShort TermLong TermFuelsStand StructureAgeInsect and Disease. Topography. Direct Influences: WindSteep slopesIndirect Influences:Forest composition and structurePrecipitation patternsSoil differencesNothing we can influence we can only recognize and deal with it..
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1. Fire Behavior, Risk and HazardPublic Land Management Agencies Bark Beetle and Lodgepole Pine Workshop Bob Means
Wyoming BLM – Forestry and Fire Ecology
06/13/07
2. This,
3. Or… This
4. Fire Behavior Basics Causes of Stand Replacement Fires
Topography
Slope
Drainages affecting wind patterns
Vegetation patterns
Weather
Short Term
Long Term
Fuels
Stand Structure
Age
Insect and Disease
5. Topography Direct Influences:
Wind
Steep slopes
Indirect Influences:
Forest composition and structure
Precipitation patterns
Soil differences
Nothing we can influence – we can only recognize and deal with it.
6. Weather Short term weather conditions:
Influences in growth of fine fuels
Amount and timing of precipitation and “dry” vs. “wet lightning"
Long term weather/climate:
Drought periods
Climate change can equal long term vegetation change
Again, nothing we can influence – we can only recognize and deal with it.
7. Fuels Stand Structure:
Lodgepole pine is a long return interval fire regime – it doesn’t burn unless conditions are right.
Although aspen in Colorado are within the Historic Range of Variability (HRV) – the acres are at the lower end.
Stand Age:
Lodgepole pine matures and stands start becoming more fire prone at about 120-150+ years in the Rocky Mountains. Extensive stand replacement fires occurred in Colorado in the mid to late 1800’s.
Insects and Disease:
Part of the ecosystem.
Not out of line with historic records.
8. Fire Behavior in Lodgepole Pine
Fire behavior in Lodgepole pine ecosystems tends to be all or nothing – crown fire or slow moving surface fire. Fire behavior tends to increase with the age of the stand.
The two primary successional lodgepole pine roles in this area are the:
1- Dominant seral – Lodgepole is the dominant cover
type with a vigorous understory of shade-tolerant
species.
2- Persistent – Lodgepole forms the dominant cover
type with little shade-tolerant species establishment.
9. Fire Behavior in Lodgepole Pine Young stands (<70 years) tend to exhibit low fire behavior unless:
1- It’s under a period of prolonged drought, or
2- There is an understory of shade tolerant species (subalpine and other true firs and spruce- ladder
fuels).
Older stands become more flammable because:
1- Dead, down fuels accumulate on the surface.
2- Insect infestations increase.
3- Shade tolerant species become more established.
10. Ecological State Lodgepole pine within this region is within it’s natural ecological condition (Condition Class 1).
Because the system is not “Out of Whack”, we must look at risk and hazard as major factors in the decision making process.
11. Risk vs. Hazard Risk:
The chance (probability) of fire starting as determined by the presence and activity of causative agents.*
Lightning
Human
Hazard:
Any real or potential condition that can cause injury…., or damage to equipment or property.*
Forest structure, age and condition
Fuels Complex – Surface and Aerial – ladder fuels, resistance to control, crown fire.
Values at Risk
Watersheds
WUI
View-sheds
*NWCG Glossary of Fire Terms
12. Risk and Hazard
Both Risk and Hazard vary temporally and spatially.
This variation can be seasonally, annually or over long periods of time.
Dynamic not Static.
13. Risk Can you change the probability of wildfire occurrence?
Human Caused fires -in a limited fashion, Yes.
Prevention and Education programs
Aggressive pursuit of damages in human caused fires
Influx of growing numbers of residents and visitors always increase the risk of human caused fire.
Lightning Fires - No
14. Hazard Can you mitigate the fuel hazard across the entire landscape and thus change the probability of fire spread, reduce fire behavior and reduce the threat to values at risk?
No
Why?
Money/Funding
Number of acres affected
Timeframes required for change
Ecology of the Lodgepole Pine
15. Values at Risk When discussing risk in this arena, we are describing the probability of an event occurring (wildfire) combined with potential negative effects as defined by humans.
To initiate effective wildfire mitigation actions you need to correctly identify the values at risk – cultural, social, economic, ecological, etc..
This involves working with your local, state and federal cooperators – the Community Wildfire Protection Plans (CWPPs) are set up to do this for the WUI.
16. How to Mitigate Wildfire Hazard
Identify the value(s) at risk.
Prioritize.
Develop specific, focused projects that modify forest structure to reduce wildfire hazard.
17. Tools to Assist You CWPPs
This should be what the community feels is important.
Flammap
Shows a static picture of fire behavior on the landscape. Includes Minimum Travel Time (MTT) and Treatment Optimization Model (TOM). Does not account for spotting. Good for showing pre and post (planned) treatment affects on fire spread.
Farsite
Can use to show fire spread on original and modified (planned) landscape, uses a weather stream (not static, but historic). It also shows spotting.
LANDFIRE,GIS and Weather data layers
Using the most current, accurate and complete information is essential for both the spatial and temporal data– Quality not Quantity
18. Flammap Tools
19. Farsite Tools
20. Potential Types of Stand Structure Modification #1 When modifying a stand - evaluate the entire stand structure, not just the red needle trees.
What is the age of the stand.
Mountain Pine Beetle prefers trees over 4-5” DBH – often when the needles drop there will be a healthy understory of reproduction.
Is there encroachment by spruce or firs (ladder fuels).
Is there an aspen component.
Is there a large dead and down component in the surface fuels.
Treat the stand to bring it back to an earlier seral stage
21. Potential Types of Stand Structure Modification #2 Modify stand structure within aspen stands.
Aspen is “natures greenstrip”.
Changing the structure of older stands that are being encroached on by conifers and moving them to an early seral state will decrease flammability of the stand and create a natural break that will last 50+ years.
22. Potential Types of Stand Structure Modification #3 Use point protection techniques around values at risk.
Modifying forest stand structure in limited areas around points at risk or along the most probable travel route of the fire will reduce the risk of wildland fire impacting the specific value at risk (WUI).
Note: This also requires that the WUI being protected implement FireSafe practices to protect themselves.
23. In Conclusion Focus
Your funds and time are limited, you have to prioritize based on Values at Risk.
Communicate
With all stakeholders.
Educate
Both external and internal.
Mitigate
Where appropriate.
Using good ecological science.
Using good silviculture.