LIVING LANDMARKS / Protecting Those Mighty Oaks

Although California is better known for its moody beaches and redwood forests, oak-studded grasslands and hillsides are its most characteristic landscape.

But over the last 150 years or so, enormous numbers of oaks, including many truly grand specimens, have been destroyed to make room for agriculture and residential tracts--which favor the same flat bottom lands and rolling hillsides.

A 1988 study by the U.S. Forest Service estimates that California has lost more than 1 million acres of oak woodlands. Today, there are 7.5 million acres of oak woodlands throughout the state. It’s estimated that another 250,000 acres could be lost to development by the end of the century.

In the San Fernando Valley region, many residents have special feelings for these gnarled and ancient trees, whose girth and wide crown of branches give them a distinctive appearance. Indeed, one of the early names for the Valley was El Valle de los Encinos --Valley of the Oaks.

Residents also have fought to protect the trees, filing lawsuits or forming human rings to block developers’ bulldozers. When Santa Clarita, which put an oak on the city seal, incorporated in 1987, the City Council’s first official act was passing a moratorium to protect the trees.

ALL ABOUT OAKS

Oaks are flowering plants of the genus Quercus , a Latin name taken from the Celtic words quer --for fine--and cuez , which means tree. They have several common characteristics, including a fruit known as an acorn, and a capacity to live for centuries.

Of 300 to 500 species of oaks worldwide, 18 exist in California--nine of them trees and nine shrubs.

Among the most common in the Valley region are the valley oak, coast live oak and canyon oak.

GROWTH RATES

There is little data matching oak tree age with height or girth because slope, soil nutrients, climate and other highly variable factors are often more important than age. But generally, here are growth rates for coast live oaks, which are generally full grown by age 100. 100 years: 65 feet* 75 years: 55 feet 50 years: 46 feet 25 years: 23 feet 15 years: 14 feet 5 years: 5 feet * Measurements are from ground to top of highest branch.

PROTECTING THE OAKS

Various municipalities have passed ordinances protecting oak trees, including the city and county of Los Angeles. In general, these laws prohibit building too close to oaks or cutting them down without a permit. Agoura Hills, Calabasas and Santa Clarita have more rigid guidelines. In Calabasas, for example, one cannot prune, transplant or remove an oak without a permit, which runs about $300.

VALLEY OAK ( Quercus lobata)

The book “Oaks of California” describes valley oaks as “the absolute monarchs, steadfast lords of the countryside, governing the landscapes in which they reside.” Grandest in age and size, valley oaks are also the most besieged--since they occupy the prime lowland real estate that has been chewed up by housing tracts. * Height: Crown of branches can reach 100 feet. * Size: Trunks sometimes 6 to 7 feet in diameter. * Bark: Thick checkered patterns the texture of alligator skin. * Habitat: Thrives in deep, rich soil. * Leaves: Two- to four-inch leaves with blunt, deep lobes and soft felt-like hairs. They release a woodsy aroma when crushed. * Longevity: Can live 400 to 600 years. Trees with trunks only three or four feet in diameter may be 150 to 250 years old.

OAK OF THE GOLDEN DREAM

California’s first gold strike occurred in 1842 near this oak located off Placerita Canyon Road outside Santa Clarita. Francisco Lopez, who is said to have had a premonition he would make a discovery, found gold clinging to the roots of wild onions he collected.

OAK OF PEACE

Mexican General Andres Pico, while encamped beside this oak in what is now Bonita Drive in Glendale, sent an envoy to meet with Col. John C. Fremont on Jan. 12, 1847. The next day he marched to the Cahuenga Pass to surrender, bringing an end to the Mexican War.

LANG OAK

Believed to be 1,000 years old, the Lang Oak is located on Louise Avenue, just south of Ventura Boulevard in Encino. This coast live oak has a thick canopy 150 feet across and a trunk 24 feet in circumference. The city of Los Angeles declared it a historic and cultural monument in 1963.