show menu

Can Caltrans transition to toxic-free management?

Before Europeans came to Sonoma County the land was managed by indigenous peoples. The land may have looked “wild and untamed” to the European eye, but all of the forests, grasslands, and rivers were actively tended in ancient tradition. Trees and shrubs were pruned at a particular time to make the best food and basket materials; grasslands and forests were burned to reduce wildfire fuel and encourage beneficial plants. This continued until about 200 years ago when the Sonoma Mission and Fort Ross were established, changing the primary human relationship to the land from cooperation to extraction.

Modern challenges and toxic-free land management

Today, land managers face new challenges building from the lineage of prior relationships between humans and nature. Roads and railway lines need to be maintained for visibility, vegetation in man-made parks needs to be tended, and a complex matrix of property rights needs to be navigated for fire safety. The agencies responsible for land management are chronically understaffed and underfunded. For decades, synthetic (laboratory created) weed-killing pesticides like RoundUp™/glyphosate were a main tool; however, when the public demanded safer alternatives, Sonoma County and city government agencies listened and either banned or significantly reduced their use. Most of the public land in Sonoma County is now managed without toxic chemicals.

Our state highways are not toxic-free

Despite great progress in Sonoma County, RoundUp/glyphosate are the primary tool used by Caltrans for killing brush along Sonoma County’s State Highways (CA-101, CA-116, CA-12, CA-37, CA-128, and CA-1). The environmental and human health consequences of these synthetic herbicides are well researched and documented. RoundUp/glyphosate is a known human carcinogen that the US Centers for Disease Control and Prevention recently found in 80% of all adults and children. Other synthetic herbicides that Caltrans uses are known to cause developmental harm to humans, are not readily biodegradable, contaminate groundwater, and are highly toxic to aquatic life/fish.

Caltrans pesticide spraying directly risks our health

Many of the roadside areas managed by Caltrans are ditches that flow directly into natural waterways. These roads run through rural communities, directly past the doorsteps of businesses and homes, and along bicycle lanes. Spraying occurs during the daytime and on weekends when pedestrians and bikers are using the roadways. As a state agency, Caltrans is exempt from many local rules and is allowed to spray pesticides with far less oversight and environmental precautions than other entities in Sonoma County.

Change is possible in Sonoma County

Mendocino and Humboldt Counties passed resolutions over 20 years ago, and Caltrans has not used synthetic weed killers since, except in emergency circumstances. Caltrans land managers in Humboldt and Mendocino have found a way to replace the toxics with well-timed mowing and grazing operations, a practice that is more in line with indigenous land management strategies. The same methods could be used in Sonoma County. For example, Sonoma County Transportation and Public Works (TPW) does not use any pesticides in West County and used only 8 gallons of herbicides to manage all County roads in 2021. For comparison, Caltrans used over 745 gallons of herbicides on Sonoma County’s State Highways in 2021.

Make yourself heard

By heeding the time tested lessons of indigeous land management and utilizing safe non-toxic methods, we can live in safe and healthy environments. Sonoma Safe Ag Safe Schools (Sonoma SASS) is actively advocating with local and State agencies for safe, non-toxic, and environmentally friendly solutions to road management in Sonoma County. You can find out more and sign a petition at:


Glyphosate is listed as a human carcinogen:

Concerns over pesticide safety leads to local bans:

Product Safety Labels of products that Caltrans uses in Sonoma County

Guardian Article: Disturbing: Weedkiller ingredient tied to cancer found in 80% of US urine samples

Mendocino tells Caltrans to stop using pesticides

We've moved our commenting system to Disqus, a widely used community engagement tool that you may already be using on other websites. If you're a registered Disqus user, your account will work on the Gazette as well. If you'd like to sign up to comment, visit
Show Comment