When Lightning Strikes: Counting on Disturbance, Planning for Succession

Abstract

In July 1988 lightning flashed deep within Yellowstone National Park. Grass browned to a crisp by the driest summer on record burst into flame. Needles crackled as the fire climbed nearby lodgepole pines (Pinus contorta) and spread from crown to crown. The wind rose, pushing fire and the acrid smell of smoke ahead of it. From a distance, the fire rumbled like a train. Closer, it roared like a jet engine, sucking in air to feed 200-foot towers of flame, spewing forth columns of smoke and embers that landed as far as 2 miles away (Billings Gazette 1995). Fifty fires started in the park that summer. By the time winter's snows put out the last pockets, more than a third of the park had been burned (National Park Service 2006). Debate raged: Was the blaze a natural stand-replacing fire, such as had last occurred in the eighteenth century, or had it been caused by decades of fire suppression? What was unmistakable as soon as the next summer, however, was that the forest was coming back. Wildflowers bloomed in the nutrient-rich ash. Millions of tightly sealed lodgepole pine cones had burst open in the flames, releasing their seeds. In between the charred trunks of their parents, these seeds sprouted into a new forest (fig. 8.1).