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- Tropical Fossils in Alaska | Geophysical Institute
Paleobotanist Jack A Wolfe of the United States Geological Survey at Menlo Park, California, has found a number of tropical rain forest fossils along the eastern Gulf of Alaska These include several kinds of palms, Burmese lacquer trees, mangroves and trees of the type that now produce nutmeg and Macassar oil
- Cottonwood and Balsam Poplar | Geophysical Institute
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
Why take a chance with exotics, when native trees have proven their ability to survive? Several reasons prompt testing of foreign tree species Human activities often create and maintain new, sometimes artificial habitats that native trees are not adapted to Exotics may have strong wood, large fruits or straight boles that are lacking in the
- Pollen season arrives, blame the trees | Geophysical Institute
The air is rich with pollen because spring is the mating season for trees The first step in a tree's reproductive dance is to release sperm, safely held in the center of a pollen grain Trees release an incredible amount of pollen to improve the odds of finding a female flower
- The Turkey and the Tambalacoque Tree - Geophysical Institute
The elderly trees still produced seeds, but none of the seeds gerrninated, even when carefully tended under ideal nursery conditions It was tempting to think the old trees were incapable of producing healthy seeds, but Temple didn't accept that reasoning For one thing, the seeds (and their encasing fruit) looked fine
- More on Why Tree Trunks Spiral | Geophysical Institute
Granted, not all trees exhibit the same twist, but the majority of them do The phenomenon can be likened to the claim that water will always spiral out of a drain in a counter-clockwise direction in the northern hemisphere
- Hoarfrost Formation | Geophysical Institute
By late winter, intricate buildups of hoarfrost crystals have formed on wooden poles and other objects Warming rays of the sun cause evaporation of whatever frost may have formed on the south side of vertical poles and trees Conduction within metal poles causes enough heat transfer to entirely remove the hoarfrost crystals from the pole surface
- The secret life of red squirrels | Geophysical Institute
Stan Boutin has climbed more than 5,000 spruce trees in the last 30 years He has often returned to the forest floor knowing if a ball of twigs and moss within the tree contained newborn red squirrel pups Over the years, those squirrels have taught Boutin and his colleagues many things, including an apparent ability to predict the future
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