Western hemlock tolerant of living life in the shadows

Fastest.

Strongest.

Survival of the fittest. When push comes to shove in nature, usually the weak or meek don’t survive. And in the case of trees, the towering giants bask in the sun and shade out their competition — at least in theory.

Waiting in the shadows of some towering Douglas fir and western red cedar are inconspicuous western hemlock. Often recognized by their droopy tops, western hemlock survive where many other species cannot — in the shade.

By no means are western hemlock shade-loving trees. Instead they are shade tolerant trees. Western hemlock grows abundantly in the shade of mature trees waiting for them to topple and then they bolt upwards to the open canopy.

The growth rings of a hemlock (or any tree for that matter) shows exactly when the tree came out of the shadows. Growth is slow in the shade as the closely-spaced growth rings attest. Once there is an opening in the canopy, the hemlock grows rapidly upwards and outwards as the wider growth rings showcase.

If a seed lands in a favorable open location it can’t compete with the rapid growth of red alder, Douglas-fir and other species. Instead, western hemlocks grow slowly in the shade, often for decades, waiting for an opening.

The ability of western hemlock to grow in the shade gives it an advantage over other species that need fire, logging or other disturbances to create sun-filled openings.

The other advantage that western hemlock harbor is their prolific seed crop. Even though each cone is less than one inch long, it holds 30 to 40 tiny seeds. And by producing cones at a young age of 25 or 30 years old, western hemlock produce more seeds in a lifetime compared to other conifers.

Prolific seeds crops help ensure that at least a few seeds germinate. Western hemlock seeds can germinate and grow in a variety of substrates from moss to rotten stumps to anyplace that stays moist. Many western hemlock seedlings can be found growing on moist “nursery logs” with their roots extending down into the soil.

Compared to other conifers, western hemlock have shallow root systems that make them susceptible to being blown over in high winds. And compared to other conifers, western hemlock attain a smaller size of approximately 200 feet.

Size isn’t a factor though for the variety of animals that forage on western hemlock trees. Pine siskens, crossbills, chickadees and deer mice eat the tiny seeds. Porcupines and some squirrels eat the bark while deer and elk eat the foliage and twigs.

Western hemlock is also a favorite nesting location for birds amid the fern-like foliage.

The foliage of western hemlock grows is feathery, flat sprays that lend to the delicate-looking branching. Distinctive to western hemlock are small, flat needles of unequal lengths ranging from one-quarter to three-quarters-of-an-inch.

But most people recognize the drooping top of the tree which acts as a weather vane since the topmost branches bend away from the direction of the prevailing wind. Of course, the hemlock has to be tall enough to be exposed to the wind and not down in the shade protected by towering conifers.

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