Weed Free Feed     






Approval of Feed Grain Mills and Storage Facilities








 What is a noxious weed? 

In California, biologists of the California Department of Food and Agriculture recommend plants for listing, after consultation with outside experts and the Agricultural Commissioners of California's counties (CACs). If a plant is found to probably be "troublesome, aggressive, intrusive, detrimental, or destructive to agriculture, silviculture, or important native species, and difficult to control or eradicate", the Department will designate the plant as a noxious weed.

The CDFA (California Department of Food and Agriculture) has three main weed control programs: 1) Weed and Vertebrate Program which involves detection, control and containment or eradication of "A" rated noxious weeds; 2) for detection and eradication of the aquatic weed hydrilla, the Hydrilla Program; and, 3) Biocontrol Unit which focuses on the more widespread weeds in categories "B" and "C".

All weeds on California's 130 plus noxious weed list have a rating. The overall rating system is NOT based on how bad a weed is -- all weeds are considered 'bad' -- but rather on overall distribution throughout the state. Ratings and formal definitions by the CDFA are:

  • "A" rated weeds are normally limited in distribution throughout the state. Eradication, containment, rejection or other holding action at the state-county level. Quarantine interceptions to be rejected or treated at any point in the state.
  • "B" rated weeds are more wide spread. Eradication, containment, control or other holding action at the discretion of the commissioner. State endorsed holding action and eradication only when found in a nursery.
  • "C" rated weeds are generally widespread throughout the state. Action to retard spread outside of nurseries at the discretion of the commissioner. Reject only when found in a cropseed for planting or at the discretion of the commissioner.
  • "Q" rated species are treated as temporary "A" weeds. Denoting action outside nurseries at the state-county level pending determination of a permanent rating.
  • "D" rated weeds are organisms considered to be of little or no economic importance. No action. Anything not rated as a "A", "B", "C" or "Q" weed is given a "D" rating. In other words, the plant has flunked as a weed!

To review California's latest and complete weed list (dated 1-6-99) as provided by the State of California Department of Food and Agriculture Division of Plant Health & Pest Prevention Services in each category rating, go to Weed List. And for color photographs and descriptions of EACH plant on list, go to Weed Photos & Descriptions.

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