Concord, CA Landscaping Rules: Weed Ordinances (2026)
Key Facts
- Requirement
- CA Food and Ag Code §5004 authorizes control
- Requirement
- Contra Costa County Ag Commissioner enforces
- Requirement
- Priority weeds: yellow starthistle, artichoke thistle, medusahead
- Requirement
- Notice required before county abatement
- Requirement
- Owner billed for abatement costs
Summary
Property owners must control noxious weeds identified by the Contra Costa County Agricultural Commissioner under California Food and Agriculture Code §5004. High-priority weeds in Concord include yellow starthistle, artichoke thistle, and medusahead. Non-compliance can trigger state abatement action.
5004. “Noxious weed” means any species of plant that is, or is liable to be, troublesome, aggressive, intrusive, detrimental, or destructive to agriculture, silviculture, or important native species, and difficult to control or eradicate, which the director, by regulation, designates to be a noxious weed. In determining whether or not a species shall be designated a noxious weed for the purposes of protecting silviculture or important native plant species, the director shall not make that designation if the designation will be detrimental to agriculture. (Amended by Stats. 1992, Ch. 556, Sec. 1.
Full Breakdown
California Food and Agriculture Code §5004 authorizes county agricultural commissioners to maintain noxious weed lists and require property owners to control designated species. The Contra Costa County Department of Agriculture enforces this program in Concord and prioritizes weeds rated A (highest eradication priority) and B (control required in uninfested areas) by CDFA. Common noxious weeds in the Concord area include yellow starthistle (Centaurea solstitialis), artichoke thistle (Cynara cardunculus), medusahead (Taeniatherum caput-medusae), perennial pepperweed, and purple loosestrife. Property owners with infestations can receive notice from the Agricultural Commissioner requiring treatment by mowing, tillage, herbicide application, or manual removal.
Non-compliance can result in the county performing abatement and billing the property owner. ConFire's weed abatement program addresses fire-fuel concerns (grass height) while the Ag Commissioner handles invasive plant concerns. Both can enforce concurrently. Property owners are also responsible for preventing the spread of weeds onto neighboring properties, and may face civil liability if their neglect causes infestation on adjoining land. Herbicide use must comply with California Department of Pesticide Regulation rules and label restrictions.
Frequently Asked Questions
Which weeds must I remove in Concord?
Can I use herbicides on noxious weeds?
Sources & Official References
Other rules in Concord
How Concord compares: Cities with the Strictest Weed and Property Maintenance Rules·California rules heatmap·Compare Concord to another location·View the California landscaping rules overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.
Weed Ordinances in Nearby Cities
How other cities in Contra Costa County handle weed ordinances.