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- Northern Tree Habitats - Geophysical Institute
They examined the present range of lodgepole pine and decided that the tree could survive in interior Alaska if given a chance Lodgepole pine grows from southern California to the Yukon, in environments varying from rainy seacoasts to dry inland mountaintops, because genetically different strains have developed
- 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
- More on Why Tree Trunks Spiral - Geophysical Institute
Prevailing winds, in most of the tree-growing northern hemisphere, are from the west Combine these factors, and the westerly wind pushing on the thicker south side of the tree, year after year, causes an asymmetrical wind loading which slowly twists the tree around in the observed direction
- 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
- Mummified forest tells tale of a changing north
The mummy trees of northern Ellesmere Island include a trunk of a pine tree four feet long and six inches in diameter Each of the trees was at least 75 years old when it died The ancient forest holds samples of the last real trees in the area before it became too cold and dry to support large plants, Barker said
- Witches Broom - Geophysical Institute
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 new needles of the broom A strong sweet odor, which is easily recognizable, usually accompanies the maturation of these pustules
- Trees for a Cold Climate - Geophysical Institute
Back on the ground, I did a little research on why so few tree types grow naturally in the neighborhood Winter's extreme cold easily eliminates some tree species hardy elsewhere Oak, ash, and elm endure occasional severely cold temperatures in the contiguous forty-eight states because they can produce chemicals that serve as natural antifreeze
- The majesty and mystery of Alaska yellow cedar
Probably because of chemical compounds within the tree like nootkatin that emit the pleasant odor and tint the wood yellow, Alaska yellow cedar endures like no other tree in the state In a 1997 paper on the endurance and possible usefulness of dead Alaska yellow-cedar trees, researchers Kent McDonald and Paul Hennon concluded it was good stuff:
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