The Arcata Community Redwood Forest

The Arcata Community Redwood Forest
Life in Northern California is impacted by the beauty of the majestic Coastal Redwood and its Ecosystem

Tuesday, April 26, 2011

Coast Redwood Germination and Growth

Three Redwood Relatives

The Coast Redwood has only two close relatives, the Giant Sequoia and Dawn Redwood. Although the Coast Redwood has been cultivated elsewhere, this tree naturally achieves its majestic heights and lush groves only in one place in the world -- a 450-mile strip along the Pacific Coast of North America. The trees prosper in this mild climate zone, where winter rains and summer fog provide an even temperature and a high level of year-round moisture.  

Redwoods are a hydrostatic marvel. They can siphon water upward to great heights, fighting gravity and friction every inch of the way. And during the dry summers in California, the coast redwoods actually create their own "rain" by condensing heavy fog into drenching showers that provide welcome moisture to the roots below.

In addition, scientists believe that redwoods take in much of their water directly from the air, through their needles and through canopy roots which the trees sprout on their branches. Lofty "soil mats" formed by trapped dust, needles, seeds and other materials act like sponges to capture the water that nurtures these canopy roots. Moisture from fog is thought to provide 30% to 40% of a redwood's water supply. 

Young redwoods use sunlight so efficiently (3-4 times more than pines) that they can grow even in deep shade. But with full sunlight and moist soil, a redwood sapling can grow more than 6 feet in a single growing season!

The coast redwoods are the tallest living species on Earth. Often they can reach heights of 300-350 feet and diameters of 16-18 feet. More than a dozen trees exceeding 360 feet in height are now growing along the California coast.

The redwood's thick bark, with deep furrows running the length of the trees, is a rich reddish brown. It is this bark that gives the redwoods their excellent fire-resistant quality. 

Coast Redwood Needles
The dark green leaves are needle-like and grow flat off the branches. Small cones, usually about an inch long, hang from the branch tips.

Redwood Seeds
Redwood cones release tiny brown seeds when mature. (They're so small that it takes about 125,000 to make a pound!) A single tree may produce six million seeds in a year. Of these seeds, less than 5% germinate, and of these, very few actually grow into seedlings. Redwoods are also capable of sprouting from the roots of parent trees, from dormant buds in the burls at the base of a tree, or from fallen trees. As well, if a tree is cut or burned, a family circle of trees ("fairy ring") may sprout up from the stump. These sprouts, because of already established root systems, grow more vigorously than seedlings and so are the more common form of reproduction. In fact, successive generations of sprouts are really "clone trees". Thus the genetic information of an individual redwood may be thousands of years old, dating back to the first parent. Will grow in USDA zones 7-10.

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