Flowering Rush (Butomus umbellatus)

Category A Weed

Flowering rush family (Butomaceae)

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Stem

  • To 5 ft. tall flower stalks

    Leaves

    • Thin, lance-shaped, triangular in cross-section, up to 40 in. long, may twist towards the leaf tip

      Flower

      • Flowers grow at the end of tall, cylindrical stalks in umbrella-shaped clusters of 20 to 50 flowers; individual flowers have 3 large pink petals and 3 small pink sepals under the flower that look like flower petals, 9 stamens and 6 pink pistils.

        Root

        • Fleshy rhizomes that grow trailing below the ground; bulbils (bulb-like plant sprouts) form at base of flower stalks and roots

          Other

          • Grows along lake shores, slow-moving rivers and streams, irrigation ditches and wetlands; no known occurrences in Nevada.
          • Perennial, spreads by rhizomes, bulbils and seed
          • Grows upright in shallow water and submerged in deeper water up to 9 ft. deep
          • Although it resembles a true rush, flowering rush is in its own family and can be distinguished by its pink flowers.

            Control

            • Carefully dig up plants, removing all rhizomes and bulbils
            • Mid-summer applications of imazamox or imazapyr under calm wind conditions have been reported to be effective; repeat treatment may be required

              Images

              Mature plant
              Rhizomes
              Stem

              Flower