near the Golden Gate Park panhandle
This Australian native is the harbinger of spring in San Francisco. It is the earliest tree to flower, putting out brilliant yellow blossoms in January. (As a native of northern New York, I still find it jarring to associate January with spring.) The tree is popular for its feathery, blue-gray foliage, although the ‘Purpurea’ variety has lavender new growth.
Bailey’s acacia is one of the fastest-growing San Francisco street trees, quickly reaching 20–30 feet in both height and width. Like most fastgrowing trees, however, it is short lived, typically surviving no more than 25 years. Known as Cootamundra wattle in Australia, this plant is native to a small area near the town of Cootamundra in New South Wales. It is a woody shrub in the wild, but it can be trained to grow as a tree.
Acacia melanoxylon
BLACKWOOD ACACIA
One of the largest of San Francisco’s street trees (to 40 feet in height, and much higher under ideal conditions), blackwood acacia is also one of the most common. It was planted heavily throughout the city in the 1960s and 1970s—so many large, mature specimens are now found citywide. The tree is evergreen, with dark brown bark and dense gray-green “leaves” 3–5 inches long, though they actually are not leaves but enlarged leaf stalks called phyllodes. (Botanists believe that phyllodes are a moisture-preserving adaptation to a dry climate.) In February and March, the tree produces an abundance of globular, pale yellow flowers that put out a great deal of pollen.
LOCATION: 1 Northwood Dr./Montecito Ave. in Westwood Park; also at 740 Masonic Ave./Hayes St.
Blackwood acacia is well adapted to San Francisco’s coastal climate and will grow (rapidly) almost anywhere on city streets, as it is not afraid of sidewalks. In fact, just the opposite is true: this tree’s aggressive roots will crack and lift sidewalks, which helps explain why in recent years it has been planted less frequently. Nevertheless, this is a good choice where a large, fast-growing tree is desired.
Blackwood acacia is native to the forests of Tasmania and southeastern Australia. It has always been an important timber tree in its native zone, and the tree’s hard wood made strong boomerangs, clubs, and shields for Australia’s aboriginal people.
Mary Ellen Pleasant and Her Blue Gums
MARY Ellen Pleasant, an African American woman often called California’s “Mother of Civil Rights,” planted the row of mature blue gums (Eucalyptus globulus) at 1661 Octavia Street, near Bush Street, in Pacific Heights. Though born a slave in 1817, she came to own a sprawling 30-room estate at this address, which has been called the western terminus of the Underground Railway that helped to usher fugitive slaves to freedom in pre–Civil War times.
In fact, once freed herself, Pleasant spent many of her early years helping fugitive slaves escape the American South. Pursued by the law, she headed to gold rush San Francisco in 1852, where with her business acumen she parlayed an inheritance from her first husband into a small fortune. She used her wealth to continue supporting African American rights. In 1868, long before the civil rights battles of the next century, Pleasant brought a lawsuit against two San Francisco streetcar lines that had denied her the right to ride because of her race. Her suit ultimately went to the California Supreme Court, where she won the right for all African Americans to ride the streetcars.
Later in life, Pleasant suffered tabloid-driven scandals and financial reverses. She died in San Francisco in 1904 and is buried in Tulocay Cemetery, north of the city, in the town of Napa. All that is left of her opulent mansion is the row of blue gum eucalyptus she planted in front of her property on Octavia Street. Set in the sidewalk amid these trees, a historical marker identifies the blue gums as something special—a part of San Francisco’s history.
Eucalyptus globulus
BLUE GUM EUCALYPTUS
LOCATION: Main Post of the San Francisco Presidio (this Centennial Tree was planted in 1876 by the U.S. Army to celebrate the country’s 100th year)
Native to a small range in Tasmania and southeastern Australia, the blue gum is likely the most common nonnative tree in California. Introduced to California in 1856, the fast-growing tree was planted extensively by pioneers hoping to make a fast buck from timber plantations (a mistake, as it turned out, because the wood of the blue gum is not well suited for sawn timber). The blue gum has since naturalized and become common in California—too common for some native-plant enthusiasts, who push for its eradication. Others (myself included) are not so doctrinaire; I associate eucalyptus with California and could not imagine the state without them.
The blue gum is one of our largest trees: its towering crown can reach 150–200 feet in ideal conditions, and in its native Tasmania, the tree is known to reach 300 feet. The leaves of blue gums undergo an interesting change in shape as trees mature. The waxy juvenile leaves produced in the tree’s early years are silvery blue and rounded, occurring in opposite pairs on the branch. The deep green adult leaves are sickle shaped, thick, and leathery, and they hang vertically from the tree’s branches. This makes them perfectly adapted to the California coast’s dry but foggy summers. The leathery leaves retain moisture, and their vertical sickle shape causes the condensing fog to drip onto the ground, delivering moisture to the tree’s roots.
Blue gums are a major source of eucalyptus oil, which has disinfecting properties and is used in a number of products. The oil is extracted from the twigs and leaves of the tree. A row of mature blue gums on Octavia Street in Pacific Heights has an interesting San Francisco history; see “Mary Ellen Pleasant and Her Blue Gums” on the previous page.
Schinus terebinthifolius
BRAZILIAN PEPPER
The Brazilian pepper is a fastgrowing, vigorous evergreen tree that is well adapted to city conditions. It has glossy, dark green compound leaves composed of 5–13 leaflets, forming a rounded crown resembling that of a carob tree. The female trees (infrequently planted on city streets) produce clusters of red berries, often used in Christmas wreaths. A shrub by nature, this tree does not develop a single straight trunk unless trained to do so—many examples of “crazy straw” Brazilian peppers are found where the trees have enjoyed only intermittent care. Attention should also be paid to their canopies, which need thinning to reduce risk of breakage in winter storms, since, like many fast-growing trees, Brazilian peppers have brittle wood. Native to southeastern Brazil and northern Argentina, the Brazilian pepper has become an invasive pest in many semitropical areas. In southern Florida, it covers some 700,000 acres, and the tree cannot be legally sold or imported in Florida or Texas.
LOCATION: 832 Alvarado St./Hoffman Ave. in Noe Valley; many
