Friends of Sausal Creek
Forests Have Replaced Watershed Grasslands

by Martha E. Lowe

Early descriptions, photographs, and drawings of the Sausal Creek watershed depict a nearly treeless landscape covered by grassland and chaparral. Except for the redwood forest along the ridges and the oak woodlands in the flatlands, trees were once confined to creeks and drainages.

The first explorers arriving in the East Bay were mistaken in the belief that they entered a wilderness. The Ohlone, who inhabited the Bay Area for thousands of years, actively managed their environment through the use of fire. Frequent burning interrupted the process of plant community succession whereby one community, in the absence of disturbance, gradually replaces another. Fire helped shape the distribution of vegetation in the watershed, favoring the grasslands and oak woodlands that contained foods and materials important to the Ohlone.

The arrival of the Spanish put an end to the Ohlone way of life, removing regular burning from the watershed. Grazing by Mexican and then European cattle partially replaced fire in maintaining grasslands and oak woodlands. In the absence of fire, however, chaparral and trees would have begun to replace grasslands.

The first Euro-Americans, attracted to the Sausal Creek watershed by its redwoods, clearcut that magnificent old-growth forest and other economically valuable trees in less than 20 years. By the time logging ended, the watershed's growing human population faced a serious wood shortage. In 1849 the situation was so bad in San Francisco that firewood sold for a phenomenal $40 a cord. Faced with a lack of timber for fuel or building, people planted trees.

Congress soon recognized that the rapid expansion of settlers in the relatively treeless West had engendered a national timber shortage. They established Arbor Day in 1872. The Timber Culture Act followed, requiring homesteaders to plant a percentage of their 160 acres in trees. Tree planting thus became a patriotic duty.

Those who came here from forested lands may also have planted trees for aesthetic reasons. An 1875 horticultural article described 34 species of eucalyptus collected by an Oakland nursery owner:

... with one among them [the blue gum eucalyptus ubiquitous in the hills today] suited for the crests of those apparently barren hills away in the distance. The eyes of our friend lighted with enthusiasm as he pictured the day when that landscape would be relieved and the whole country fertilized by these magnificent trees.

Our now-forested hills are largely the result of fire suppression and tree planting in the late 1800s. With this shift in vegetation, we have lost productive grasslands and chaparral. Our human-made forests have reduced much of the watershed's original biodiversity.

Though often rare, many native plant species are still present in the watershed. The Friends of Sausal Creek are actively engaged in identifying and locating plant species and intact plant communities so we can begin to restore native biodiversity in the watershed. Join us!

The next Friends of Sausal Creek meeting is on Wednesday, August 18, from 7 to 9 p.m. at the Dimond Library. Our next restoration workday will be on Saturday, August 21, from 9 a.m. to noon in Dimond Park. For more information, call Anne Hayes, 231-9566.