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Storms continue to pound drought-stricken California this week, creating some hazardous conditions. Last Friday heavy rains caused dangerous mudslides in areas that were severely burned by wildfires. California had one of its worst wildfire seasons on record this year and more rain raises fear that the worst of the mudslides is yet to come.
Amy Quinton of Capital Public Radio reports.
AMY QUINTON, BYLINE: Just an hour east of Sacramento, trucks carrying burned timber in the Eldorado National Forest roar past. Chainsaws buzz in the distance, but U.S. Forest Service ecologist Becky Estes says besides humans, not much else in this forest seems alive.
BECKY ESTES: We're standing in an area that - this is going to be probably 100 percent mortality of the trees.
QUINTON: The King Fire burned nearly 100,000 acres here in September. In this steep river canyon, 50,000 acres burned in one day. The pine trees are black and lifeless. Not one pine needle remains on the branches.
ESTES: The amount of needles that were consumed off of these trees in the time frame that it happened then was much more of a severe case than the Rim Fire.
QUINTON: The Rim Fire, which burned into Yosemite National Park last year, was the largest wildfire ever in the Sierra Nevada, but the damage isn't limited to the trees.
ERIC NICITA: What I really want to do is get some unburned soil - what it's supposed to look like - and on the way here, I couldn't find it.
QUINTON: Eric Nicita, scientist with the Forest Service, is looking for earth that wasn't scorched by the fire. It's difficult. A quarter of the soil in the fire-damaged area is what scientists call a high-severity burn.
NICITA: What we do is, we just kind of scrape away the dirt and see what's going on.
QUINTON: Nicita digs two to three inches into the black dirt before he can find any living plant roots. He says he's never seen a fire burn so much soil so severely.
NICITA: What influences the burn severity is the amount of organic material that's on the ground. If it's a nice, clean forest, you know, with little build-up, those generally don't burn that hot.
QUINTON: But fire hadn't burned the vegetation on the ground here in 120 years. That combined with the steep slopes of the canyon, the constant wind and drought conditions kept the fire raging. But the damage has only just begun. Nicita says water now beads on the charred soil and runs off.
NICITA: Even though we've had what, five or six inches of rain, we're only getting soil wetting down about a half an inch to an inch. We're dusty-dry down below an inch.
QUINTON: Forest Service crews are busy with backhoes, moving rock to divert flows along roads. But rain has already cause falling rocks and debris.
Barrett McMurtry is a Forest Service engineer.
BARRETT MCMURTRY: There's been equipment mobilized here around the clock keeping up with the debris flow as it comes off the hillside.
QUINTON: So far, mudslides in the burned area have been small. But the Forest Service says it's only a matter of time. Eric Nicita points up to an almost vertical slope next to heavily-traveled road. Down-slope from the road is the Rubicon River.
NICITA: The Rubicon is known for its fisheries. It's got a great trout run and that's at high risk, also. And we evaluated that, but there's not really much we can do to reduce the risk to that.
QUINTON: The potential problems from erosion are widespread. Reservoirs and hydropower dams are within the burn area. The Forest Service had hoped that California's drought would make mudslides unlikely, but now that the rains have come, the drought has made the mudslide danger worse. Forest Service crews will likely be dealing with mudslide damage from the King Fire for years to come.
For NPR News I'm Amy Quinton in Sacramento.
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