Discovering The Historic UIowa Trees: A Guide To The UIowa Elms

Above: An elm-lined street in St. Paul, MN, before most of the trees were killed by Dutch Elm Disease. Although the American elm persists in forests and pockets of cities and towns, Dutch Elm Disease ...

Paleobotanist Jack A. Wolfe of the United States Geological Survey at Menlo Park, California, has found a number of tropical rain forest fossils along the eastern Gulf of Alaska. These include several kinds of palms, Burmese lacquer trees, mangroves and trees of the type that now produce nutmeg and Macassar oil.

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The Klukwan giant belies the belief that trees tend to get smaller the farther north one goes. Both balsam poplar and cottonwood have value for fuel wood, pulp and lumber.

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Scrawny trees offer less wind resistance, and a tree growing on permafrost couldn't develop much of a root system to prevent its being blown over. Thus the higher-latitude form would be more likely to survive gusts and produce offspring.

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In an earlier column , I asked if any readers could explain why the grain in trees seemed to spiral up the trunk-in a clockwise direction. That is, spiral marks in old trees crack open from the upper right to lower left around the trunk. Professor (now Emeritus) Neil Davis, the originator of this column, posed the same question in this column over ten years ago, and it's time for an update. I ...

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A swath of dead, tilted and broken trees now makes obvious the trace of the Fairweather fault that broke in July 1958 to devastate Lituya Bay and nearby parts of southeastern Alaska. Sagging or tilting of the ground along a fault trace causes trees there to tilt or even fall.

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