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 ...
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 ...
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.
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.
It is not possible to foretell if tamarack may some day become a commercial crop, but one thing is certain: the "spruce that dies" each fall has some unique qualities that make it a desirable tree for ornamental, subsistence and commercial uses in interior Alaska.
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 borrowed the key from a researcher with UAF’s Agricultural and Forestry Experiment Station, Woodward has invited me to join him inside the chain-link fence.
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 as tree thinning, pruning, setting out hormone traps for beetles, and getting rid of piles of logs that attract beetles.
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.