Houndstongue (Cynoglossum officinale)

Category A Weed

Borage family (Boraginaceae)

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  • Up to 4 ft. tall and covered with long hairs


    • Alternate; resemble a hound's tongue; lance-shaped, 1-12 in. long, 1-3 in. wide, rough texture and covered with long hairs; edges (margins) lack teeth and lobes

    • Leaf stems (petioles) on lower but not upper leaves; leaves decrease in size from bottom to top of plant


      • Purplish-red flowers with 5 petals; occur in clusters

      • 4 nutlets (seeds) per flower, 0.25 in. long and brownish at maturity; covered with short prickles that can attach to clothing or animal fur


        • Thick, deep taproot


          • Grows best in moist areas; often found in pastures, roadsides, fencelines, waste areas and along waterways; known to occur in Elko, Eureka, Humboldt and Lyon counties

          • Biennial, but sometimes annual or perennial; reproduces by seed

          • Toxic to livestock, especially horses; has a distinctive odor that may cause animals to avoid


            • Mowing or tillage prior to seed production is effective

            • Apply 2,4-D, metsulfuron, picloram or imazapic to actively growing plants prior to bloom


              Houndstongue Plant
              Mature Plant
              Houndstongue Flower
              Houndstongue Rosette
              Houndstongue Seed attached
              Seed attached
              Houndstongue Seed flower
              Seed flower
              Nevada Noxious Weed Field Guide
              Nevada Noxious Weed Guide