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- Cottonwood and Balsam Poplar | Geophysical Institute
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 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
- Northern Tree Habitats - Geophysical Institute
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 of those, plus jack pine, balsam fir and lodgepole pine Since northern Canada and interior Alaska share the same grueling climate and extremes of daylength, why are the Canadian tree species absent from
- Trees as Earthquake Fault Indicators | Geophysical Institute
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 within the past thousand years is important in establishing earthquake risk and for predicting future earthquakes
- More on Why Tree Trunks Spiral | Geophysical Institute
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 tends to be thicker on the south side of the tree because of better sunlight
- Feltleaf willows: Alaska’s most abundant tree | Geophysical Institute
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 sprouts canoe-shaped green leaves that feel fuzzy on the underside
- Tree line changes on the Kenai Peninsula | Geophysical Institute
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, during which the insects killed 30 million mature spruce trees on the Kenai and a wide swath of southern Alaska
- The majesty and mystery of Alaska yellow cedar | Geophysical Institute
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 transports water and nutrients — snaking up the trunk A few of its blue-green feathery leaves flagged from the top of what otherwise looked like a snag
- Tree Rings and History | Geophysical Institute
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 and thin during the winter These annual growth rings are easily discernible (and countable) in cross-sections of the tree's trunk In good growing years, when sunlight and rainfall are plentiful, the growth rings
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