Larix Lyallii | Derivations on a survival regime

Original Publication DATE: 8/10/2011

Conifers possess highly derived adaptations that allow them to flourish on continental land masses north and south of the 45th parallel—to the arctic tree line. They also grow in similar regions with decreasing latitude, like the various cordilleras of western North America. Though they comprise less than 1% of all plant species (~630), they define 30% of the forests on Earth. In order to survive in colder climates conifers must be able to handle temperature and moisture extremes. As a cat preens its fur, most conifers care for their needles. These waxy progeny are coddled when energy is diverted from other tree functions to maintain needles—often for many years. This heavy investment must allow needles to endure both high and low temperatures while at the same time regulating water loss during the warmer months. Also, because most conifers are evergreen, they are not inhibited by late spring or even summer frosts which might otherwise kill the leaves of a less cold-adapted species. Angiosperms–many of which are deciduous–generally inhabit lower elevations and warmer regions where they spend less time and energy in leaf production and maintenance and can therefore allocate resources to grow faster and pioneer oft-disturbed landscapes more rapidly. It it these two generalized survival regimes that had me confused on a recent backpack into the Pasayten Wilderness where there is a conifer that has blazed a unique path for survival on the edge of the Washington State alpine tundra.

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The alpine tundra of the Pasayten Wilderness is characterized by small hummocks decorated with diminutive heaths and grasses with the much taller conifers surviving on only the fringes of this landscape.

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