Vegetation Management Plan Delays

by Ann Thomas

A lengthy planning effort to establish guidelines for managing vegetation on county open space is in recess after contentious public hearings this fall which concluded with the acceptance of a plan to be used as a guidance document, its original intent. Environmental review will be conducted for specific projects that need it.

The vegetation management plan for the 18,900 watershed acres owned by the Marin Municipal Water District, stalled in mid-2015 but is restarting with environmental review of the district’s new draft plan.

The ongoing controversy over herbicide use is the cause of the de-lay, even though some very limited herbicide use is necessary to control a few of the invasive plants that are harmful to Marin’s native ecosystem, increase fire danger, and can add to flood risk. Friends of Corte Madera Creek Watershed supports using the Integrated Pest Management (IPM) process to establish strategies to ad-dress invasive infestations. IPM is a science-based, decision-making process allowing herbicide use when all other methods would be ineffective.

Mount Tamalpais, viewed from Loma Alta. Photo by Charles Kennard

Mount Tamalpais, viewed from Loma Alta. Photo by Charles Kennard

Open Space Preserves
Marin County Open Space District began work on their Vegetation and Biodiversity Management Plan (Plan) in 2009. The Plan includes years of data collection on plant re-sources and vegetation science, and describes district goals of balancing public access, fire fuel reduction, and natural resources protection.

An Environmental Impact Re-port (EIR), with a price tag of more than $400,000, was prepared and the dual package came to the County Parks and Open Space Commission, then to the Board of Supervisors, sitting as the Open Space District Board of Directors, in October. Both groups received numerous letters and verbal comments asking decision-makers to not accept the EIR or the Plan but instead support a total ban on herbicide use.

The advisory citizen commission, recommended certification of the EIR and adoption of the Plan. On October 18, the Open Space District Board of Directors/Board of Super-visors, bowing to anti-herbicide activism, did not certify the EIR, and accepted but did not adopt the Plan. As a result of not certifying the EIR, environmental review will now have to be done annually on a project-by-project basis, although many projects do not need environmental review.

Opposition has focused on glyphosate, one of the least toxic of effective herbicides available. Glyphosate is one of hundreds of substances identified by one monitoring agency as a probable carcinogen. It is in the same category as alcoholic beverages, emissions from high-temperature frying, sunlight, chemo-therapy drugs, and red meat: sub-stances for which consumption or exposure should be limited. The assessment of carcinogen-causing potential is not based on an assessment of risk or dose, so its validity is questioned by many experts.

Use of herbicides by open space professionals is carefully targeted to the harmful plant, and rigorous protocols are followed to protect applicators and to post advanced notices of applications at public access points to the area treated. Herbicides use in county parks is strictly confined to areas with natural habitats; no herbicides are used on play-grounds, picnic areas, or other areas of heavy public use. Herbicide use on county open space is estimated to be one percent or less of the county total, with personal and commercial use of chemicals contributing the bulk of use.

The open space district, operated separately from county parks, comprises 34 preserves. Those in the Corte Madera Creek watershed include the following: Baltimore Canyon at the headwaters of Larkspur Creek, Cascade Canyon above Fairfax, King Mountain, Loma Alta, Ring Mountain in Corte Madera, and the White Hill and Bald Hill preserves overlooking Fairfax and San Anselmo.

Unlike the county’s park system, which invites recreational use, the open space areas are set aside primarily to protect their natural habitat in addition to providing recreation. County open space preserves are adjacent to the back yards of about 3,300 residential properties and any uncontrolled vegetation on district lands adds to residents’ wildfire risk.

Water District Watershed
The water district, serving most of Marin County, had not used herbicides for a decade, which has resulted in the explosive spread of broom and other problem plants that cannot effectively be controlled without herbicides. The district, over several years, prepared a new management plan to update its 1995 version and it included a full range of IPM options.

In July 2015 the district’s Board of Directors, who were consistently lobbied by anti-herbicide groups, abruptly stopped review of this plan and directed consultants to prepare a new version that does not include consideration of herbicides in the portfolio of strategies. This revised ‘Biodiversity, Fire, and Fuels Integrated Plan’ was issued in September and is expected to soon begin undergoing environmental review at the end of January, although this could be changed, and the comment period for members of the public will run for 30 calendar days.

Friends is part of a coalition of organizations supporting use of IPM to protect our natural habitat. Information is on the group’s website: