SAN FRANCISCO – An intense battle is building over a little-known plan to cut down thousands of eucalyptus and other trees in urban forests here and at a city-owned golf course in Pacifica.

Both camps believe they know what's best for some of San Francisco's most stunning landscapes, including Mount Davidson, Mount Sutro and Glen Park Canyon.

It's a clash of environmental visions, with each camp maintaining that it's right.

"Initially, the program sounded wonderful, but now it's becoming quite dreadful," said Jacquie Proctor, a member of the Miraloma Park Improvement Club, which represents neighbors on Mount Davidson, where plans call for removing 1,600 trees.

On one side is the city's Natural Areas Program, also called NAP. Created in 1997 as part of the city's Recreation and Parks Department, it oversees one-fourth of the city's parkland. On the other side are its critics, including the San Francisco Forest Alliance, which wants to protect the trees targeted for removal.

NAP sees its mission as restoring natural areas and protecting biodiversity by removing non-native trees and ground cover such as French broom. The targeted trees are mainly eucalyptus, first planted by philanthropist Adolph Sutro in the late 1800s.

Restoration, the way NAP officials see it, includes replacing the non-natives with natives such as oaks, coyote brush and ferns.

"There are thousands of papers on the impact of invasive species and how – when biodiversity is limited – the ecosystem falls apart," said the program's director, Lisa Wayne. "You get many fewer animals using the areas."

The alliance counters that the program's approach is costly and damaging to songbirds, coyotes and other wildlife inhabiting the areas where non-native vegetation has taken root.

"When your average taxpayer hears these tree-removal plans, many are angry," said the alliance's chairman, Eric Miller.

NAP's website says the program selectively thins stands of small eucalyptus to let sunlight reach other plants, typically targeting trees that are spreading into native habitat areas.

Some trees that threatened the growth of live oak, creekside willow and other natives have also been cut down, the website says. The program's budget for the current 2011-2012 fiscal year is $1.37 million.

Wayne, the program's director, said she doesn't know how many trees have been removed thus far. NAP's plan for the next two decades, she said, calls for taking out 5 percent of the city's trees in the areas that the program oversees.

That plan calls for removing 18,448 trees in all – 15,000 from San Francisco-owned Sharp Park in Pacifica and 3,448 from the city. The city's Planning Commission and its Recreation and Park Commission must sign off before any plan moves forward. Appeals would go before the Board of Supervisors.

City officials said it would be some months before the final report is completed, after which the Planning Commission will hold a public hearing.

Critics question not only the program's expenditures in budget-tight times but also the native plant advocates' rhetoric.

" 'Restoration ecology' is a euphemism for a kind of gardening informed by an almost cultish veneration of the 'native' and abhorrence of the naturalized, which is commonly characterized as 'invasive,' " Arthur Shapiro, a distinguished professor of evolution and ecology at UC Davis, wrote city planning officials last October.

A small project, Shapiro added, would be worthwhile. "Wholesale habitat conversion is not. … Wholesale tree removal, except for reasons of public safety, is sheer folly," he wrote.

Wayne countered that it's not the program's goal to cut down all the trees.

"We have to continually strike a balance between protecting the native plant resources and protecting the tree canopy," she said. "It is like a land-use war is going on, and some people don't want to see any change."

Critics note that the program's pledge to replace trees on a 1-to-1 ratio includes no promise to plant those trees where the others were removed. They also say that the draft report doesn't quantify, as required by law, how much carbon would be released into the atmosphere by the trees' removal.

But the program has many allies, including thousands of volunteer participants.

"We support what NAP is doing – restoring native biodiversity so San Francisco's native critters and plants will survive into the future," said Arthur Feinstein, president of the Sierra Club's San Francisco Bay Chapter.

Such statements don't sway Proctor and other opponents."We didn't realize … that NAP believed non-native trees such as Monterey cypress should be removed," she said. "We are fighting now to preserve our natural open spaces as a peaceful oasis in the middle of one of the country's most densely populated cities."

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Susan Sward is a freelance writer based in San Francisco.

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