A SHORT LIFE HISTORY OF A LONG LIVED TREE
We marvel at the great age of the giant sequoia. We are tremendously impressed as well by the physical dimensions of this tree. But, one of the most remarkable facts to contemplate is its huge bulk in relation to the minute seed from which it grows. It has been calculated that the General Sherman tree contains over 600 tons of weight in its trunk, yet this tree grew from a seed so small that 3000 or more weigh but one ounce. From seed to giant trunk represents a growth doubling in weight over 36 timesa final product nearly 58 billion times the weight of the original seed!
This tiny seed, a small cylindrical form encased in a membrane forming two lateral wings, is produced abundantly. Perhaps a single tree will produce a billion seeds in its lifetime.
Normally a 200 year old sequoia will produce cones, and some trees are reported to have produced infertile cones at the early age of 24. Ovoid, and from 1-1/2 to 3 inches long, they require two years to mature. They remain green on the tree until the squirrels cut them off. A few seeds may be released from the cones each year but the cones do not develop the rich brown color until they are cut and allowed to dry. Thus, a given tree retains cones of many years, dropping a few seeds from some cones every season.
Most of the cones, however, are harvested in the fall by the busy chickaree or Douglas squirrel. When cut down, these cones rapidly dry out, the thick scales open up, and the seeds are released within a few weeks. As you follow the sequoia trails, find a fresh-looking brown cone. A sharp blow of the cone against the heel of the hand will usually dislodge a few of these tiny seeds for your examination.
Many of the seeds are consumed by squirrels, birds, and insects. Others disintegrate by decay on the ground, and only a very few ever germinate and produce seedlings. Before the seed will grow it must fall upon exposed mineral soil, and in a place fairly open and exposed to the sun. This is why you will find no seedlings beneath the shade of the heavy forest canopy, nor where the thick duff covers and protects the soil. But where an opening is made in the forest and the soil is exposed, as where a giant falls, or along road and trail cuts, new seedlings appear by the hundreds.
Most of the seedlings succumb to trampling, insects, and competition with other plants, and are thus thinned by nature. Eventually, however, one or several seedlings of a new generation persist to continue the forest.
The youth of the species is not merely a small edition of the mature giant, but is quite different in appearance and has a character of its own. Look for an evenly tapered, sharply conical tree, with thick foliage reaching down to ground level. Check your identification by examining the needlesshort, sharp, somewhat awl-shaped, and overlapping like shingles around the twigs and branchlets. In their regular sharp conical form, the young sequoias are among the most beautiful of all the trees of the forest.
As the trees grow higher and higher, the lower branches, as is the case with most forest trees, shaded from above, deprived of life-giving sunlight, lose their needles and are pruned away by the normal growth of the trunk. The effect, by the time the tree is a hundred feet high, is that of the same sharp conical youthful tree, but now carried on the top of a straight, bare trunk. The deep furrowed cinnamon red bark is not yet apparent, and these younger trees display a grayish rather stringy bark.
By the time the tree approaches its ultimate height, more of the numerous small branches of the crown are lost. Those that remain expand greatly, rebranch, and finally form the rounded crown that marks the early mature tree. This situation prevails, with the older mature trees displaying their straight, massive, red trunks, and a comparatively few heavy and rebranched limbs bearing the dense foliage of the crown.
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The Sawed Tree near Grant Grove is an example of the balance and recuperative powers of the sequoia. Cut almost all the way through by loggers, it did not fall, and stands today perfectly balanced, supporting abundant foliage and with part of the saw cut already covered with new growth.
When a sequoia falls, the sap wood is attacked by insects and is destroyed in a few score years. The heart wood may persist for many centuries without apparent decay.
A harmful practice may not show its results in the human body for a score or more years. A giant sequoia lives 50 times as long as man, and a harmful practice may require 50 score years to show its effect on the big tree. Our only safe procedure is to guard and protect the sequoia environment in every possible way.
Last Updated: 02-Feb-2007