Point Reyes Light- May 11, 2000

Homeowners, not ranchers, the main users of pesticides

Recent spraying of pesticides by West Marin ranchers trying to control thistle has prompted complaints about the practice, although ranchers aren't the main users of the roughly 35 tons of toxic chemicals that are applied every year to control weeds, bugs, and other pests in Marin County.

Most of the pesticide use in the county occurs in East Marin, inside buildings and on private lawns and gardens. In 1998, the latest year for which data is available, the state Department of Pesticide Regulation recorded that about 70,000 pounds of herbicides and pesticides were applied in Marin.

Over half that amount - 39,870 pounds - was applied by exterminators working in homes and other buildings. The next largest repository was gardens and lawns, where 9,867 pounds of pesticides was applied.

Almost 9,000 pounds of herbicides were sprayed on rights-of-way along state roads, power lines, in the watersheds, and elsewhere in the county.

Sulfur on vineyards

By comparison, Marin grape growers used 6,368 pounds of pesticides in their vineyards, mainly in the form of sulfur, an organic fungicide. Olive growers used nearly 500 pounds of pesticides in their orchards, and ranchers put 1,209 pounds of chemicals on their pastures.

Agricultural commissioner Stacey Carlsen, whose office monitors the use of pesticides by ranchers, growers, and all professional landscapers and exterminators, said it is one of the most highly regulated practices in California.

Anyone who applies pesticides professionally must get a license from the state, then register with the county Agricultural Commissioner. Ranchers who wish to use pesticides must consult a licensed pest control advisor and pass an examination if they are to apply the chemicals themselves, Carlsen said.

Furthermore, licensed professionals and ranchers must report to the Agricultural Commissioner each time they apply pesticides. They are subject to sanctions and possible criminal charges if they are discovered violating safety codes or misusing the chemicals, he said.

Household toxics

Perhaps more dangerous to public health and the environment are household weed, bug, and varmint killers that are applied without any oversight, said Carlsen, who estimated that as much as 10 tons of over-the-counter pesticides are used annually by Marin residents.

Challenging all this chemical use is a broad coalition of local organizations known as Marin Beyond Pesticides. Carol Steritt, a member of the organization, said the group is working to educate the public about the health and environmental risks associated with pesticide use.

Marin Beyond Pesticides also promotes alternative pest control methods, such as using goats to graze on invasive species, and is working to eliminate the use of pesticides in schools. The group has scheduled its next meeting for 7 p.m. Wednesday, May 24, in the San Geronimo Valley Cultural Center.

The National Park Service, County of Marin, Marin Municipal Water District, MALT, and other public officials are also reconsidering their management of invasive, non-native plants through the so-called Weed Management Area, which coordinates weed-control efforts by landowners in Marin and southern Sonoma County.

Point Reyes National Seashore

Participants in the Weed Management Area follow the edicts of Integrated Pest Management - detect and map problem areas, set priorities, and deal with them in the least harmful manner, explained Kim Cooper, a vegetation manager at the Point Reyes National Seashore.

Cooper said the National Seashore has made a priority of controlling thistle, pampas grass, and French and Scotch broom in the park. Because these plants grow spottily in often remote places, rangers usually pull them out without resorting to chemical herbicides, she said.

Conceding that herbicides have their place, Cooper said the Weed Management Area meetings have done much to promote cooperation but have yet to find consensus on when and where it is appropriate to use chemicals to control weeds.

Point Reyes Light Cover | News | Coastal Traveler