Northern Tree Habitats - Geophysical Institute
Apr 3, 2026 · 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 …
Tree Rings and History | Geophysical Institute
Feb 12, 2026 · A tree's age can be easily determined by counting its growth rings, as any Boy or Girl Scout knows. Annually, the tree adds new layers of wood which thicken during the growing season …
More on Why Tree Trunks Spiral | Geophysical Institute
Apr 3, 2026 · 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: Foliage …
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 …
Tree line changes on the Kenai Peninsula | Geophysical Institute
Feb 6, 2008 · The gradual change in tree line is one of many that people have noticed on the Kenai Peninsula in recent years. The most obvious is the 1980s-to-1990s Spruce bark beetle invasion, …
Cottonwood and Balsam Poplar | Geophysical Institute
Apr 3, 2026 · 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 …
Pollen season arrives, blame the trees | Geophysical Institute
May 7, 2008 · The airborne invaders are grains of tree pollen, specks so small that it would take eight of them to cover the period at the end of this sentence. The air is rich with pollen because spring is the …
Bark beetles take Connecticut-size bite out of Alaska | Geophysical ...
Feb 26, 2004 · Knowing that, forest managers might be able to anticipate an outbreak and plan tree harvests ahead of the beetles or try preventative measures that might work on small outbreaks, such …
Visit to an exotic tree plantation in Alaska | Geophysical Institute
Jun 18, 2021 · The two-acre exotic tree plantation is part of a much-larger “boreal arboretum” on the UAF campus, which mostly consists of native spruce, birch, aspen, poplar and willow trees. Having …
The Pinhole: Nature's Lens | Geophysical Institute
Jul 10, 1972 · Sunlight passing through minor apertures between tree leaves is focused like the rays in a pinhole camera (and, just as with a simple lens, the image is upside-down).