Mayor Gavin Newsom’s promise to plant more than 5,000 trees this year has taken root, according to a new report, but questions remain about how The City will maintain its existing forest.
Newsom pledged two years ago to plant new trees throughout The City and this year 5,167 were added, 4,280 on public streets, according to a new report from The City’s Urban Forestry Council. San Francisco has roughly 700,000 trees — including 106,000 on public streets with room for 120,000 more, particularly in low-income neighborhoods — according to the report.
But 51 percent of San Francisco’s trees are young — with trunks less than 6 inches in diameter — raising questions about just how many new trees are surviving, Forestry Council member Milton Marks said. The council’s report urges San Francisco to focus more intensely on keeping existing trees healthy.
“It’s very difficult to know the net increase of trees,” Marks said. “If trees aren’t surviving, how many you plant doesn’t really matter.”
Roughly one-third of The City’s street trees are maintained by the Department of Public Works. Trees in city-owned parks are the responsibility of the Recreation and Park Department. In addition, an array of agencies — from the San Francisco Unified School District to the port — along with private contractors are responsible for tree upkeep.
Finding the money for tree care has been a constant struggle, said Jim Lazarus, vice chair of the Recreation and Park Commission.
“We have not had enough funding for tree maintenance for a long, long time,” Lazarus said. However, the 2008 Neighborhood Park Bond voters approved in February includes $4 million for maintenance and planting, he said.
“The only way to truly make San Francisco a green city is to set and meet ambitious goals,” Newsom said in a statement regarding his tree-planting initiatives.
While Marks is worried about making sure younger plantings survive, many residents are keeping a close eye on the health of San Francisco’s aging trees — especially after a redwood branch fell and killed Kathleen Bolton on a windy April day in Stern Grove.
“The trees in McLaren Park haven’t had any grooming, and every week we have more limbs coming down,” said Franco Mancini of Friends of McLaren Park. “It’s Russian roulette.”
The City’s trees by the numbers
700,000: Approximate number of trees in San Francisco
106,000: Number of street trees
120,000: Empty street sites where trees could be planted
5,167: New public trees planted in 2007-08
115: Number of tree species in San Francisco
51.5: Percent of trees with a diameter of 6 inches or less
$110: Increase in property value for each tree on the property
Source: San Francisco Urban Forestry Council's annual report, September 2008