20 August 2012

WILDFIRE


Today marks the 24th anniversary of Black Saturday, the worst single day of conflagration during the 1988 Yellowstone wildfires.  Hotshot firefighting crews from around the nation were flown in to battle the blazes, which blackened 793,880 acres ~ 36 percent of Yellowstone National Park.

Under conditions with no human interference, wildfires are part of a natural cycle which consumes dead trees, shrubs, grasses, and downfall in habitats ranging from forest to prairie, clearing space and adding nutrients to the soil so that younger growth can gain a foothold.  However, a misguided policy within the National Park Service and US Forest Service called for the suppression of all wildfires, regardless of size or lack of impact on humans.  The result, over the course of decades, was an accumulation of dry, dead fuel within the nation's forests.  It was a disaster waiting to happen, and in the dry, hot drought of 1988 conditions were ripe for a perfect firestorm.

After the 1988 battle was over, policy was changed to allow wildfires within the nation's parks and forests to run their course, so long as they do not threaten human life or property, and so long as they are not started by human carelessness or arson.  Pulling back from suffocating over-management is a healthy step, one which ought to be applied to wildlife as well.

As it happens, I was clued in to the importance of fire as a cleansing agent in nature, long before the Yellowstone fires.  From 1978-1982 I worked for The Nature Conservancy as caretaker at the Canelo Hills Cienega Preserve, am upland marsh with a permanent spring-fed stream, surrounded by oak/juniper woodland and grassland.  The community (see image above) is a relict ecosystem, a surviving remnant of habitat that was once more widespread throughout southern Arizona.  In their turn, Spanish, Mexican, and American ranchers allowed overgrazing which contributed to soil erosion and the lowering of the water table, draining many cienegas.

Canelo is home to several endangered species of fish and flowers, an oasis for native wildlife and for migratory birds.  My work there included maintenance of the historic adobe ranch house, outbuildings and fences, greeting visitors, monitoring the resident flora and fauna, and patrolling against poachers during hunting season.  My TNC supervisor was H.L. Bill, a quiet and very wise man who once worked cruising timber in the South.  It was he who taught me the need to allow most wildfire to run its course.

As it happened, the marsh grasses of the cienega had accumulated a dead overstory, much like the forests in Yellowstone.  No natural fire had swept the cienega in many years, and the overlying dead grasses were smothering the endangered Canelo Ladies Tresses, a low-growing orchid.  It was decided to invite a nearby Forest Service fire crew to do a controlled burn, to rejuvenate the cienega.  I was present to direct the operation, choosing which areas to burn and which to protect with the crew's water trucks.

The burn was a huge success by any measure.  Those blackened acres were a riot of green by the following spring, as marsh reeds, grasses, and sedge repopulated.  And the numbers of orchids quadrupled over the pre-burn count.  The Forest Service crew did a superb job of containing the burn so that no riparian growth was threatened.  It was good practice for them, and much-needed assistance for the cienega.

I often think of those years.  I left the preserve to pursue my degree in Ecology & Evolutionary Biology at the University of Arizona, and thence to other pursuits.  But the cienega appears from time to time in my dreams, always being threatened by human encroachment.  And in my heart I'm always right there to protect this remnant wetland, and always will be.

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