for National Geographic News
GRASS CREEK, WyomingHere in the thirsty Absaroka Range of the
Rockies, the foothills are toasted brown, except where last summer's
raging wildfires scorched nearly 14,000 acres to charcoal. Those
mountainsides are now green with grass, but it is sparse and stunted
from one of the worst droughts in a century.
The two-year drought, which intensified last winter when snow packs dropped to 40 percent to 60 percent of normal, has left creeks dry and forced ranchers to sell large numbers of their breeding herds. Yet the fires generated regrowth of native grasses, which land managers and biologists believe will be sufficient to sustain the wildlife.
This is the lucky side of the Rockies.
West of Wyoming, in the Great Basin that lies between the Rockies and the Cascades-Sierra Nevada Mountains, the outlook is far grimmer. In the five states of that region, cheatgrass is turning vast parts of the Great Basin into wasteland.
One third of the 75 million acres in the Great Basin are dominated by invasive weeds, according to Don Smurthwaite, a spokesman for the National Interagency Fire Center in Boise, Idaho. The worst invader is cheatgrass, a botanical immigrant from the Russian steppes that slipped into America in the 1890s with wheat seed and livestock.
Six months ago, the Western Governors Association reported that the invasion of weeds already has caused U.S. $138 billion in economic damages, Smurthwaite said. "On average, 4,000 acres a day are being overtaken by weeds," he said. "That's a staggering figure."
Cheatgrass packs a double whammy. It grows rapidly after a wildfire, choking out native plants. In addition, it dries out early and turns into a highly flammable mat that covers the rangeland, setting the stage for more wildfires.
Last year, the cost of fire suppression totaled U.S. $1.8 billion, according to Jack Sept, also with the National Interagency Fire Center.
In this year of extreme drought, he noted, the cheatgrass dried before spring ended, and wildfires have already been burning with an intensity usually not seen until the height of summer.
Wildfires are a natural part of the ecosystem in the inter-mountain west. Usually set by lightning, the fires burn off excessive brush and trees, opening grassy meadows for wildlife, birds, and livestock. Because controlled fires can be very helpful to the environment, the U.S. Bureau of Land Management (BLM) conducts a controlled burning program.
But once cheatgrass takes over an area, the usually long natural fire cycle shrinks to recurrent episodes every three to five years, which allows the native vegetation no time to fully recover.
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