The most outstanding features of this 816-acre park are its two redwood groves. Some of the trees in these groves stand more than 300 feet tall and may be close to 1,000 years old. Madrones, Douglas-firs, and California laurels share the cool shade of the redwoods. Massive stumps and fallen trees lie covered in moss. Beneath the old-growth giants, ferns and redwood sorrel blanket the ground, and soft, decomposed redwood duff mutes all sound to a mellow hush.

Occasionally, bobcats and mountain lions stalk black-tailed deer and small animals such as raccoons, cottontails, gray foxes, skunks and chipmunks. Black bears are sometimes seen among berry bushes, and Steller’s jays, thrushes, and woodpeckers add to the restful sounds of wind in the trees.

A guide to nature on the Discovery Trail is available online.

Coast Redwoods
Coast redwoods sometimes regenerate as seedlings but more often grow from sprouts, which start easily on lateral roots or from stumps or downed logs. Young redwoods grow quickly—two to six feet a year—so that a 20-year-old tree will often be 50 feet tall and about eight inches in diameter. The species can eventually attain heights of more than 300 feet and diameters exceeding 20 feet.

Redwoods have a double defense system that keeps them healthy and often allows them to reach old age. Their bark, which can grow nearly a foot thick, protects against both fires and pests. The bark also contains tannins, which combat insects and fungi. If a fire does penetrate, the tree often becomes a partly hollow “goose pen.”

Coast redwoods’ root systems extend outward, rather than down. Their networks of lateral roots are shallow, seldom penetrating more than six feet deep but sometimes extending laterally hundreds of feet. Trees provide each other mutual support by overlapping and interlocking their roots. Even so, they are occasionally susceptible to undermining by flooding and toppling by wind.

Redwood forests once covered large parts of North America, but today they grow naturally in only three portions of their original range. Coast redwoods (Sequoia sempervirens) are found along the coast from central California to southern Oregon. Inland, giant sequoias (Sequoiadendron giganteum) climb Sierra Nevada slopes.

Sudden Oak Death
In 1995 native oak and tanoak trees began dying in coastal California. Scientists took five years to solve the mystery of “Sudden Oak Death” and discover a cause: a water mold called Phytophthora ramorum.

Since then, this non-native plant disease has destroyed millions of tanoaks and other trees and damaged many other plants like huckleberries and California bay laurel, which host the disease and help spread the spores. Although its origins remain unknown, it was probably introduced through infected soil or plants brought to California.

State Parks biologists are working to control Sudden Oak Death by removing infected trees and planting native trees that aren’t affected by the disease. However, the disease-causing spores—found on leaves, mud, and organic material—multiply and spread quickly, especially in wet weather.

The Navarro River runs through the Anderson Valley and Hendy Woods State Park. In addition to enabling human settlement and activities such as agriculture, logging, and recreation, the river and its tributaries provide habitat to thousands of animals and plants, including willows, sedges, and alders.

In a time of climate change, redwoods are an asset. Their size and longevity help them store more climate-altering carbon dioxide than other plants. Even old redwoods continue to grow, each year adding more carbon-filled wood than smaller, younger trees. After redwoods die, their rot-resistant wood keeps stored carbon out of the atmosphere for a long time

Could redwoods be harmed by climate change? Actually, they don’t seem to be suffering so far. Scientists, however, say that increasing temperatures, along with decreasing summer fog, could pose a threat in the decades to come. To find out more about the effects of climate change in California’s redwood parks, go to this Save the Redwoods League web page.