Johnsongrass (Sorghum halepense)


Category C Weed

Grass family (Poaceae)

Helpful Links

List of all Photo Credits

Stem

  • Up to 8 ft. tall; many tillers arise from crown; stems slightly flattened with prominent nodes

    Leaves

    • Up to 2 ft. long, 0.25-0.75 in. wide, white midvein and mostly hairless except near collar; ligule is membranous and tipped with fine hairs; NO auricles

      Flower

      • Seed head open and pyramid-shaped; purplish-brown at maturity

      • Seed is narrow, less than 0.25 in. long and reddish-brown to black

        Root

        • Deep, fibrous root system; rhizomes are white and fleshy with brown to purple nodes; roots and new plants often form at nodes

          Other

          • Grows best in moist soils; often found in crop fields, pastures, fencerows, roadsides, and along waterways; known to occur in Churchill, Clark, Douglas, Esmeralda, Lincoln, Mineral and Nye counties

          • Perennial; reproduces by seed and rhizomes; seedlings resemble corn and can best be identified by pulling a plant and examining the roots for an attached seed

          • Plants can be toxic to livestock after frost or drought

            Control

            • Frequent mowing or tillage is effective; burning is NOT

            • Apply sethoxydim, fluazifop or fenoxaprop to actively growing plants before boot stage, imazapic or flyphosate between boot and bloom stages 

              Images

              Johnsongrass plant
              Plant
              Johnsongrass Leaf stem
              Leaf stem
              Johnsongrass Root
              Root
              Johnsongrass Seed
              Seed
              Johnsongrass seedling
              Seedling
              Nevada Noxious Weed Field Guide
              Nevada Noxious Weed Guide