Cottonwood and Balsam Poplar | Geophysical Institute
6 days ago · 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 giant belies the …
Northern Tree Habitats - Geophysical Institute
6 days ago · Interior Alaskan forests have only six native tree species: white spruce, black spruce, quaking aspen, balsam poplar, larch (tamarack) and paper birch. Northern Canadian forests have all …
Trees as Earthquake Fault Indicators | Geophysical Institute
6 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 earthquakes occurring …
Witches' Broom | Geophysical Institute
6 days ago · 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 pustules appear on the …
More on Why Tree Trunks Spiral | Geophysical Institute
Nov 20, 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 here: …
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 neighbors to …
Burls and Human Cancer | Geophysical Institute
Dec 4, 2025 · Photograph of a section cut from a tree with 5 burls that simultaneously grew at the same level on the tree. Annual growth rings can be followed around the tree trunk at center and into each …
The majesty and mystery of Alaska yellow cedar | Geophysical Institute
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 bark that …
Feltleaf willows: Alaska’s most abundant tree | Geophysical Institute
May 25, 2023 · The most plentiful moose food in the state — and probably Alaska’s most numerous tree — is the feltleaf willow, which was once called the Alaska willow. As its name implies, the feltleaf …
Alders go their own way in autumn - Geophysical Institute
Sep 10, 2015 · But one shrubby tree does not join the party. Alders remain a stubborn green. Many won't drop their leaves until long after the snow falls. This reluctance is one of the wonders of an …