Weed Research and Information Center

Weed identification

  • Online Weed ID Tool
  • Sending samples: Weed samples collected in California can be sent to Joe DiTomaso for identificaiton. Fresh samples sent by mail should be protected from damage. To prevent rotting, do not place fresh plant material in Ziploc or sealed plastic bags. Samples pressed and dried can be sent in an envelope between two stiff pieces of cardboard. Please include all relevant plant information, such as: 1) habitat, 2) size (if sending only a partial specimen), 3) location, 4) elevation, and 5) plant characteristics which are not easily discernible from the sample (i.e. root type, flower color, etc.). Mail your sample to Joe DiTomaso :: University of California :: Dept. of Plant Sciences, MS4 :: One Shields Avenue :: Davis, CA 95616.
  • Sending samples: You may also send a plant to the UC Davis Center for Plant Diversity (formerly known as the UC Davis Herbarium) for identification. Please follow the instructions at their website: plant identification services.