The ecosystem of the Okanogan Highlands is rooted in fire ecology. These conifer forests and associated flora have evolved with fire as a natural and necessary contributor to habitat vitality and renewal. Numerous plant species exist in the
that naturally require fire in the processes of germination and to reproduce.
As an example – Lodge Pole Pine is dependent on fire for replacement. Unlike the more massive Ponderosa Pine, the Lodge Pole has little defense against wildfire. With a thin bark and growing in dense stands these trees, under the right conditions accelerate fire to the crown. Wildfire then may spread tree to tree and thus a stand-replacing fire occurs. Intense fires cause the serotinous cones of the Lodge Pole Pine to open, releasing the seeds to be able to regenerate.
The intermix of humans and fire in the Okanogan Highlands has a long history starting with the native tribes who developed the process of using landscape fires to burn off areas with the results of improving hunting and foraging as well as maintaining travel corridors. Over time as the demographics of the
Highlands shifted emphasis was
placed on fire suppression thus changing the role of fire in the area. Still
many of the natural occurring plants are highly flammable throughout periods of
the annual fire season and contribute to wildfire problems to fire managers,
firefighters, and the general community.
|Small surface fire spreading in pine needles|
Wildfire Ponderosa Pine…
Flames of a small wildfire burn at the base of a Ponderosa Pine in the timber litter surrounding the tree. Mature Ponderosa Pines are rarely affected by wildfire due to the thick bark surrounding their bole. Their needle cast encourages low intensity fires to burn beneath the mature trees eliminating brush and other competitive tree growth leading to a veranda like forest of these towering trees in their natural environment. The Ponderosa Pine and the habitat it creates plays a vital role in the fire ecology of the Okanogan Highlands.
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|Part of the surface fuels is the abundant timber litter|
Spreading Surface Fire…
Once the source of ignition in a dry vegetation environment has started combustion in receptive fuels a small fire begins spreading across a limited landscape. Sometimes this is the natural cycle of nature, a lightning fire thinning the fuels. Other times it is the carelessness of humans causing a fire with potential for great damage. In this image the lighter fuels, grasses (known to firefighters as ‘one hour fuels’) and timber litter (10 hour fuels) are carrying the fire to heavier vegetation and enhancing the wildfire spread.
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|Surface fuels have carried the fire to and ignited a small tree|
When the larger vegetation is receptive (dry enough and in specific arrangements) wildfire can spread from the one hour fuels (grasses) to the larger ‘10’ fuels (small branches and forest debris). In this case a small fir tree torches as the heat from the surrounding grass combustion sets the stage for wildfire growth.
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|Multiple trees begin to torch and launch burning embers|
Double Torch – Wilcox Fire…
As the wildfire developed and spreads across the landscape to more available fuels the complexity of the of the situation increases; temperatures rise, convection columns develop, more torching occurs and the fire begins to burn in the heavier ‘100 and 1,000 hour fuels’. A simple brush fire is developing into a more complex forest fire. I took this image mid afternoon on a clear, summer’s day but the smoke column from the larger body of the main fire was so thick it appears to be late twilight. What you see here are spot fires in the advance of the main blaze.
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|Cluster torching of multiple fuel types|
In this photograph a cluster of fir trees and a branchy, dead snag are torching. On this hot day in the
these flaming trees will launch thousands of burning embers downwind. Embers
landing far from the main blaze with start spotfires. Spotfires will grow and contribute to the
spread of the wildfire increasing the difficulty and danger of fire suppression operations. Clusters of trees torching like this are not crown fires.
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|Fireline manager calling in air attack resources to control spot fire|
Calling in an air strike…
Fire Commander calling in an air strike on this spot fire. Spotfires have to be “knocked-down” to establish control of the main fire. The over all objective is to check the spread of the wildfire by holding it against a nearby forest roadway. The torching fir in the foreground has tight-knit branch clusters caused by a disease called mistletoe, which causes deformity in the trees branches and tops. These tight clusters of fuel burn very hot once ignited and can cause problem fire behavior.
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|Heavy air-tanker making a retardant drop on a wildland fire|
I caught this pic of a heavy retardant ship (airplane) flying low and dropping it’s load of red dyed retardant in an effort to check the fire spread. Air attack resources allow ground firefighting forces to close with the wildfire with the object of containing it. This action was on the Cape Labelle Fire, near Wauconda
in the Okanogan Highlands.
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|The stage is set for a crown fire|
Beginning of a crown fire...
If burning conditions are right, and the progress of the forest fire goes unchecked a more complex crown fire may develop. A crown fire is where the fire progresses through the crowns of the trees independent of the ground fire. Conditions of a crown fire often lead to what firefighters call a “nuked” landscape. Where everything is burned, the soils scorched away and only the near branchless, black boles of trees remain standing. In this image we see a crown fire developing on the Togo Fire near
south of Danville,
Washington . Grand
Forks, British Columbia
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|The aftermath of a stand replacement crown fire|
The Aftermath of a Crown Fire...
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|Mount Leona Fire Scar - Winter|
|Mount Leona Fire - North Fork Saint Peter's Creek|
August 13, 2001
a dry thunder storm moved through the Okanogan Highlands. Lightning ignites
multiple fires, one of which was the Mount Leona Fire. It started on the north
slope of ,
within the boundaries of the Mount Leona , west of Kettle
Crest in Colville
National Forest ,
approximately 15 miles northeast of Republic, Ferry County Washington.
The fire grew to 6,144 acres and spilled over onto the northeast side of , burning in a steep and
Mountain , ponderosa pine, lodgepole pine, with areas
of heavy dead and down fuels. forest of Douglas
|Dozer used in fireline construction as a fire suppression tool|
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