CARSON CITY, Nev. - "For thousands of years, American Indians carefully tended stands of pinon pines in Nevada. The Washoe people would gather nuts in the Pine Nut Mountains and use them throughout the year to toast and make powder, stews and salves. Surviving climate changes, stands of the odd-looking trees with twisting branches and stiff needles spread through the West. But a recent phenomenon has scientists concerned.
A few years ago, researchers in several Western states started noticing shorter needles on the pines and black powdery substances around them. Then the trees started dying. "When you see those start dying, they're beyond just dry," said Kelly Redmond, climatologist with the Western Regional Climate Center in Reno. "They belong here. They're adapted to dry conditions. When they start showing stress, they're telling you there's more stress than usual."
Tree experts are trying to determine what is killing off hundreds of pinons, the state tree of Nevada. "People are starting to very much watch these patterns of mortality," said Connie Millar, research geneticist at the Institute of Forest Genetics for the U.S. Forest Service's Pacific Southwest Research Station. "We're looking at a regionwide phenomenon."
In one grove south of Gardnerville along U.S. 395, as many as 20 percent of the trees have died in the past few years. Scientists investigating the tree deaths are focusing on the effects of a four-year drought that has gripped northern Nevada and neighboring states."
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