The enclosure to the July 9th 2009 letter from UCSF’s Assistant Vice Chancellor was puzzling. It managed to concentrate a large number of questionable statements in a very small space, and will keep this blog busy for a while!

Today: Let’s talk about the risk of fire.

1. In support of the purported danger, the note refers to two actual wildfires at other locations: Mount Vision fire in Point Reyes in October 1995; and the Angel Island fire in October 2008. According to the note, “These areas have similar terrain, climate and vegetation as Mount Sutro.”

They do not.

The Mount Vision area is primarily chaparral (grasses and bushy scrub), with some forest of Douglas Fir and Pine. The Mount Vision Fire of October 1995 was a chaparral fire – a fire of the low scrub and grasses which actually would resemble the vegetation on Twin Peaks, not on Mount Sutro. In the dry season, the scrub and dry grass is extremely flammable – much more so than any tree. Caused by an illegal campfire, the Mt Vision fire involved no eucalyptus. http://www.sfsu.edu/~geog/bholzman/ptreyes/tripfire.htm

Angel Island, because of its location, has quite a different micro-climate than Mt Sutro, which is within San Francisco’s fog belt. According to the visitor information website, http://www.angelisland.org/faq2.htm “It is generally enjoys sunnier and warmer weather than San Francisco, which has many more days of fog.”

Fog photos taken in the same hour: Sutro Tower, Angel Island

The Angel Island Fire was also grass and chaparral fire – Angel Island was denuded of nearly all its eucalyptus more than a decade ago. While many talked about how terrible the fire would have been had the eucalyptus been there, the residual eucalyptus didn’t actually burn. Before the trees were cut down, the only fires seem to have been structural fires. After that, there have been at least two, in August 2006 and October 2008, both of which burned grass and chapparal.

Native plants like dry grasses and coyote bush are extremely flammable. They are part of a fire ecology. This makes sense when the chaparral is burning miles from habitation – but not so when it’s in the middle of a city.

The current plan for Mt Sutro is to open up the forest: “The forest floor will be much more open with more sun exposure and with clearings of native grasses, wildflowers, and brush.”

This sounds like a plan for increasing the fire hazard, unless UCSF is putting in an irrigation system as they have in the Native Garden. Since that garden required a $100,000 grant from the Rotary Club, it’s not clear where the funding for irrigated open clearings of dry grasses is coming from.

2. The note states, “In December 2008, the City and County of San Francisco adopted the San Francisco Hazard MitigationPlan (http://campusplanning.ucsf.edu/pdf/CCSF_Hazard_Mitigation_Plan.pdf ), which identified portions of the Sutro forest as a “Very High Wildfire Hazard” (see page C-13).”

It’s very unclear how exactly the area got designated as Very High Fire Risk. The map basically shows every eucalyptus grove in the city in red. It’s also not clear where the map comes from, since the information available on the Cal Fire website designates the area as having Moderate Risk, its lowest rating. The source document, a more detailed map from Cal Fire [ABAG] shows only one area in the forest as High Risk: The Native Garden at the summit, where the risk is in fact mitigated by the irrigation system.

[ETA (March 2013) There’s a discussion of all the “fire hazard maps” HERE. To summarize: UCSF showed three maps that purported to show fire danger, but actually were erroneous – and ignored the actual Fire Hazard map from the most reliable source, CALFIRE. The response of FEMA, which actually spoke to a CALFIRE person about the discrepancy, is HERE.]

3. There’s a reference to three fires, the latest ten years ago, that were quickly spotted and extinguished. That’s the point, isn’t it? These fires didn’t spread. Calling them “wildfires” is somewhat exaggerated. They were also all manmade, which makes one wonder about continually broadening access to the forest.

[ETA (March 2013): In the meeting regarding opening the new trail from Stanyan into the forest, Ray Moritz (who UCSF also hired as an arborist) minimized the fire danger. You can read that report HERE.]

It is apparent, when the data are examined critically, that the fire risk has been overstated – and that the planned actions will actually increase, not decrease the fire risk by introducing native grasses and shrubs and increasing the sunlight into the forest sounds. Angel Island didn’t burn until the trees were gone. San Bruno mountain had a grass and scrub fire starting from a prescribed burn.