"It's Complex" Fire Ecology & Recovery 2015 Conservation Course - Class #2 Notes

Summary of Feb 3, 2015 class by volunteer Nick Thorp

With a solid understanding of the historical role of fire in our valley and the changes that have occurred over the past 100 years under our belts, the second class moved deeper into the complexities of fire and the Carlton Complex, and examined the effect and post-fire recovery of forested areas and factors such as insects and fungus that can both impact that recovery.


Susan Prichard, a Research Scientist at the University of Washington’s School of Environmental and Forest Sciences, kicked off the evening by presenting on forest recovery and what we can expect to see in the burned landscapes around the valley. She began with a reflection on the Carlton Complex fire: its intensity, its uniqueness, and how these factors will impact recovery. An eight day stretch of 100+ degree heat…winds gusting at 30-35 miles per hour…an extremely dry land . . . all fueling a fire that grew at incredibly rapid speeds, burning 160,00 acres in a 24 hour period.


How does such an extreme fire like this impact forests? Like everything related to this fire, it’s complex. Susan framed the answer to this question by looking at the adaptations of plants to survive fire, broken down in four categories:

• Resisters:

  

  Ponderosa Pines are fire adapted

  Trees such as ponderosa pine and western larch are adapted to survive fires with their thick bark and lack of low lying branches.  In the fires of last summer, with an ember driven front that ignited trees before the flames hit, ponderosa pines, even with their adaptations, experienced an abnormal 100% mortality in some places. Without planting, recovery of these high-severity burned areas may take decades, and some of these areas may convert to grass and shrublands for some period of time.
  

  

  Burned aspens resprouted quickly after the fire

• Endurers: Plants like aspen, balsam root, and elderberry. While the above ground vegetation burns, the roots below ground can survive.  Since the fires moved so quickly, these plants should do great in recovery. In many places we saw re-growth taking place in the months and even days following the fire.
• Invaders: Plants that range from lupine, to cheatgrass, to fireweed. These plants come into open areas following a burn and are able to thrive. Some are native while others are new, invasive species that can crowd out others.
• Avoiders: Plants and trees like the subalpine fir. These survive by simply being out of harm’s way and existing in places with low fire frequency.

The second presenter of the night, Connie Mehmel, a Forest Health Specialist for the Okanogan-Wenatchee National Forest, shared how various insects (e.g., wood-borers and bark beetles) and pathogens (e.g., fungi) interact with fire. Some of these insects are attracted to the heat and/or smoke of the fire, and depending on the timing of the fire relative to the flight period of the insects (as well as some other factors), the insects can invade the burned stands. Wood borers, which feed on dead trees, generally come in first, followed by bark beetles. The bark beetles generally feed on damaged and dying trees, but can move to adjacent living trees.

Bark beetles, a natural part of the ecosystem, increase when trees are stressed

In addition to insects, various species of fungi can both be activated. For example, the teapot fungus is activated by fire and can cause damage to seedlings in the first two years after fire. . “Good” fungi, like mycorrhizal fungi, that help the roots of new saplings and other plants take hold in their beginning stages of growth can be damaged by hot fires, taking away a key natural aid to landscape recovery. On the other hand, fire can rid areas of tree-damaging fungi. For example, fire can consume the fungus responsible for various root rots.


Connie also talked about dwarf mistletoe, a pathogen that has generally become more common in our region due to fire suppression. Among other things, dwarf mistletoe causes trees to grow low branches, making a given stand more susceptible to crown fire. There is a negative feedback loop here, with fire generally killing mistletoe.

The class was filmed in four sections, all of which, plus the first class, are available here:
http://methowconservancy.org/conservation_course_2015_videos.html