The Street Trees of San Francisco

When Native Americans inhabited what is now San Francisco, the landscape consisted of large swaths of grasslands, sand dunes, and salt marshes, with only six species of trees and three types of bushes that can grow to tree size. More species of trees were eventually introduced to Mission Dolores, and after the Gold Rush, there were between 400 and 500 tree species in the area. That number is now over 500. San Francisco’s tree canopy is at approximately 13.4%, which is actually quite low compared to many other cities. There are approximately 669,000 trees in the City, with the most common being the London plane tree, the Indian laurel fig, and the New Zealand Christmas tree. Of the total trees, about 125,000 line the streets of San Francisco, with the rest being in backyards and parks.

Besides the obvious aesthetic quality trees bring to a neighborhood, there are a plethora of additional benefits. Street trees increase the curb appeal of a house, therefore increasing the property value. A study in Portland, Oregon, of the sale of houses found that on average, street trees add 3% to the median sale price of a house. Traffic noise is absorbed, and trees create a sense of privacy.

Trees produce oxygen, clean the air, and reduce global warming. Trees release oxygen, and two medium-sized, healthy trees can supply the oxygen required for a single person for a year. By absorbing greenhouse gases, trees clean the air by storing carbon dioxide in their stems and leaves. Airborne particles such as dirt, soot, and dust are also captured by trees.

Sidewalk gardens and trees reduce flooding by capturing rain. During heavy rainstorms, large amounts of water can overload the City’s combined storm-sewer system, causing polluted runoff containing chemicals in the street to get dumped in the Bay. A mature tree can store 50 to 100 gallons of water during large storms. The average tree in San Francisco can intercept over 1,000 gallons of rainwater a year.

The presence of trees has a calming effect on traffic, reducing the speed of drivers. Trees and sidewalk gardens increase revenues in shopping districts, with some studies showing consumers have a 12% higher willingness to pay for goods and services in retail areas with streetscaping. Street trees also provide a natural habitat for birds and insects.

Fortunately for us, we have two wonderful community organizations who dedicate their efforts to planting and caring for our street trees in Oakland and San Francisco. Urban Releaf is an urban forestry nonprofit 501(c)3 organization established in Oakland to address the needs of communities that have little to no greenery or tree canopy, with their emphasis on underserved neighborhoods that suffer from disproportionate environmental quality of life and economic depravity. Friends of the Urban Forest (FUF) helps individuals and neighborhood groups plant and care for street trees and sidewalk gardens in San Francisco. Since 1981, FUF has planted more than 60,000 trees, totaling almost half of the city’s street tree canopy.

Visit our garden centers for everything you need to plant and care for your trees, including loppers, folding saws, shovels, pruners, and more!