TWO MAJOR UPDATES:
1. Watch for toxic Spraying in San Mateo County without Warning. And Report!
2. We sent message in January 2026 to Supervisors and Parks regarding:
a. Parks are spraying on Endangered Mission Blue Butterfly Habitat. Does not seem to follow guidelines of Endangered Species Act.
b. Glyphosate (Roundup and other brand names) SAFETY RETRACTED by top science journal (report) (article) Glyphosate has been shown to be toxic in ultra low doses. (research)
⚠️WATCH FOR TOXIC SPRAYING of herbicides (which are pesticides) in our COUNTY and PARKS Now (~Feb-Nov) Please document and help us END IT!
Please document and send a quick email/photos. It is the power of numbers of people writing in to tell them to stop and why you care.
Spraying is often labeled “Habitat Restoration,” in the guise of poisoning weeds. Safer alternatives exist without risks to people, pets, wildlife, air, or water.
👀 If You See Spraying: Send Email:
-Protective gear -Note date, time, location
-Backpack sprayers or spray tanks -Take photos if safe
Y-ellow tape closing areas -Report what you see, people, gear, signs, etc
➡️ Leave the area immediately. -Tell them to end spraying.
Send email to Contacts: elgonzalez@smcgov.org, SMC_SupMueller@smcgov.org mdurani@smcgov.org (SMC Parks Director: Emma Gonzalez, Supervisor Mueller, Marisol Escalera Durani, [chief of staff]) Or call Supervisor Mueller’s Office: 650-363-4569, Parks Director Office: 650-363-4020
CC: egdavocates@gmail.com, pattymayall@gmail.com (El Granada Advocates, Protect Our Watershed San Mateo County)
Chemicals observed:
Glyphosate (RoundUp) (Dec 2025 safety retracted by science journal) (link)
Garlon 4 Ultra and Clearcast (Imazamox) -both harmful to pollinators, aquatic life and humans (research)
PARKS ARE SPRAYING ON ENDANGERED MISSION BLUE BUTTERFLY HABITAT
Parks claims spraying oxalis protects butterfly larvae and native lupin, but Endangered Species Law treats pesticides as habitat disturbance and requires proof of NO harm.
Herbicides used are not oxalis-specific and will kill re-seeded native lupine sprouts and other plants. As poisons, they pose obvious risk to insects and larvae.
Although described as “small amounts,” large areas are being sprayed, and even low doses of herbicides like glyphosate are toxic. These chemicals persist, drift, and run-off, expanding harm beyond the spray zone.
We are local residents volunteering to end this as many other counties have. It is time for our County public officials to prioritize protecting public health and our environment.
*Let them know what you think and visit our website for more info, spread the word and sign our petition.