One would think the Natural Areas Program would be about preserving trees in our city. It’s not. San Francisco in its pre-European state had very very few trees if any, and almost all our trees are non-native. Despite the huge benefits of urban trees, NAP’s “Significant Natural Resource Area Management Plan” (SNRAMP) wants to fell 3,500 in the city, and an additional 15,000 in Sharp Park. Here are the main areas besides Sharp Park:
- 1600 trees on Mount Davidson (this would be in addition to trees already killed by girdling and other means).
- 809 trees in McLaren Park.
- 511 trees in Bayview Park (also in addition to trees killed by girdling).
- 140 trees in the Interior Green belt on Mount Sutro (unclear whether this would be in addition to the 50 trees cut down along the Kill-trees Trail).
- 134 trees in Lake Merced (presumably in addition to an unknown number that were already felled there in 2010).
- 120 in Glen Canyon and O’Shaughnessy
- 82 in Golden Gate Park
- 15 in Corona Heights.
- 14 in Dorothy Erskine
- 10 in Buena Vista Park
- 5 in Grandview Park
- 3 in Brooks Park
- 3 on Twin Peaks
- 2 in Palou Phelps
As we noted above, there’s been deforestation under various guises, by the NAP or its supporters – or others – even while the SNRAMP goes through the approval process. A lot of trees have been killed by girdling, particularly in Bayview and on Mount Davidson. (Girdling involves cutting bark around a tree so it starves to death, sometimes over years.)
Some may have been killed by other means.
Some have been felled as “urban forest” work – for instance in the Interior Greenbelt and at Lake Merced. Trees in Natural Areas are not evaluated for whether they are a hazard, but for their condition, including “poor form.”
BUT ISN’T EUCALYPTUS A FIRE HAZARD?
No, despite the widespread belief to the contrary.
First, San Francisco is foggy or rainy round the year. Calfire considers the entire area a “moderate” fire risk – which is its lowest rating. (The other ratings are “High” and “Very High.)
Areas of dense trees, like Sutro Cloud Forest, or Mt Davidson, act like a Cloud Forest. The tall trees harvest moisture from the fog, and the forest holds this moisture in.
It has been argued that in the fall, San Francisco has sunny dry weather and this is when there’s a fire hazard. In fact, SaveSutro maintained a daily Fog Log in the Fall of 2009. Even during sunny weather – there was night fog or rain many evenings. The longest “dry” period in the forest was 7 days.
At no time did the forest dry out.
Second, even in drier climates, eucalyptus is not more flammable than other trees; and the native grasses and shrubs that are actually planned as a replacement are much more flammable than the trees.
In a firestorm caused by dry conditions and hot dry winds (which do not occur in the city) everything burns – oaks and fir, eucalyptus and pine. In fact, eucalyptus may even help fight wind-driven fires by trapping flying embers and disrupting wind flows because of its flexible crown. There’s more information about this and other myths at Eucalyptus Myths on SaveSutro.com.
Finally: Here’s the picture worth a thousand words. In a ruinous fire in Scripps Ranch in San Diego, a number of houses burned to the ground. The eucalyptus surrounding them failed to ignite. Not incidentally, the home-owners of Scripps Ranch fought to save the eucalyptus trees when the City tried to cut them down – after the fire – as a hazard reduction.