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  1. Northern Tree Habitats - Geophysical Institute

    Aug 14, 2025 · Interior Alaskan forests have only six native tree species: white spruce, black spruce, quaking aspen, balsam poplar, larch (tamarack) and paper birch. Northern Canadian …

  2. Cottonwood and Balsam Poplar | Geophysical Institute

    Aug 14, 2025 · The Klukwan giant holds the national record for black cottonwood diameter. Its nearest rival, a tree near Salem, Oregon, does hold the national height record. The Klukwan …

  3. More on Why Tree Trunks Spiral | Geophysical Institute

    Aug 14, 2025 · I eventually found a tree with a spiral lightning mark and it followed the spiral grain exactly. One tree, of course, proves nothing. "But why should the tree spiral? More speculation …

  4. Witches' Broom | Geophysical Institute

    Aug 14, 2025 · Witches' broom on spruce trees is caused by a rust disease (a kind of fungus disease). The rust lives on the spruce tree throughout the year. Each spring, small yellow …

  5. Trees as Earthquake Fault Indicators | Geophysical Institute

    5 days ago · Then using tree ring dating methods, it may be possible to date earthquakes occurring before historical records were kept. The ability to identify and date very large …

  6. The largest black spruce in Alaska | Geophysical Institute

    Aug 16, 2010 · The tree leans uphill, and its trunk is 45 inches around. When I hugged it, I could barely clasp my hands together. The largest black spruce in Alaska is a lucky tree, because its …

  7. Tamarack -- Not A Dead Spruce | Geophysical Institute

    Aug 14, 2025 · It is not possible to foretell if tamarack may some day become a commercial crop, but one thing is certain: the "spruce that dies" each fall has some unique qualities that make it …

  8. The majesty and mystery of Alaska yellow cedar | Geophysical …

    Jul 23, 2021 · A tree near one of our campsites had a crack at its base through which we could pass the folded saw. Yet the tree was still alive, with just one rope of cambium — the outer …

  9. Burls - Geophysical Institute

    5 days ago · Burls, spherical woody growths on the trunks of spruce, birch and other trees, are commonly found throughout wooded parts of Alaska.

  10. The Kodiak Treeline | Geophysical Institute

    Aug 14, 2025 · Spruce trees planted on the islands by the Russians in 1805 are doing just fine and reseeding themselves naturally, although the total tree population hardly amounts to a …