Key Identification Features of Cogongrass

Flower/Seed head

  • Cylindrical in shape
  • 2-8 inches in length (total flower or seed head)
  • Silvery white in color
  • Light fluffy dandelion-like seeds
  • Blooms from late March to mid June (flower timing depends somewhat on local climate)

Leaves

  • Blades up to 6 feet long
  • About 1 inch wide
  • Whitish, prominent midrib, that is often off center
  • Margins finely serrate
  • Some leaves are very erect, but some may droop or lie flat
  • Often light yellowish-green in color
  • Could have a reddish cast in fall/winter or brown after frost or freeze

Plant Base

  • No apparent stem
  • Leaves appear to arise directly from or close to the ground
  • Overlapping sheaths give a rounded appearance to the plant base
  • All vegetation doesn’t arise from one dense clump, instead the plants are more spread out
  • Light-green to yellowish in color, or could be reddish
  • Often a lot of thatch around base

Leaf collar/Ligule

  • Ligule is a thin-fringed membrane
  • Leaf sheaths overlapping, giving the plant a round appearance
  • Hairy (the ligule is the most hairy part of the plant, the plant base may also be somewhat hairy)

Rhizome/Roots

  • Dense mat
  • Many sharp points
  • Covered in flaky scales
  • Bright white under scales
  • Strongly segmented

Whole Plant

  • Densely growing patches
  • Tall grass (up to six feet, averaging 3-4 feet)
  • Circular infestations
  • Plants often turn brown in winter (at least partially, but may depend on local climate)