Weeds: Foxtail (Green, Yellow, Bristly) – Setaria spp.

categories: F-H Weeds

revision date: 2024-06-22 07:54

  • Family: Poaceae (Graminae)
  • Cycle: Annual
  • Plant type: Grass
Yellow foxtail.
Yellow foxtail
Photo by: D.G. Swan

Biology

Three species of foxtails are found in the Pacific Northwest: green foxtail (S. viridis), yellow foxtail (Setaria pumila), and bristly foxtail (S. verticillata). Yellow foxtail grows in clumps reaching one to three feet. The leaves are smooth, 1/8 to 3/8 inch wide, and tapering to a point. The ligule (occurring at the point where the leaf blade joins the leaf sheath) is comprised of a fringe of hairs, with numerous long hairs at the leaf base. The leaf sheath is smooth, and auricles are absent. The seeds are borne at the tops of the stems in a densely packed, “hairy” seed head one to five inches long. The greenish to brown seeds are about 1/8 inch long. Green foxtail is similar to yellow foxtail, but is generally shorter in height, has rough leaf sheaths, shorter seed heads, smaller seeds, and lacks the long hairs at the leaf bases. Bristly foxtail resembles green and yellow foxtails, but the seed heads are bristly rather than hairy, causing them to cling to clothing and animals.

Habitat

Foxtails are weeds of cultivated areas, roadsides, and waste areas. They can be a serious problem in some crops.

Management Options

Use Integrated Pest Management (IPM) for successful plant problem management.

Non-chemical Management

Select non-chemical management options as your first choice!

  • None recommended

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

  • Preemergent herbicides are very effective in controlling foxtails.
  • In areas where annual grasses are consistent problems, apply in spring when soil temperatures reach 50 to 55 degrees F.
  • Glyphosate products should be used as spot treatments only!
  • NOTE: Some ingredients listed here are only available in combination.
  • Read the label carefully on combination products to make sure the product is suitable for your specific situation.

Landscape areas

  • glyphosate
  • oryzalin
  • products containing diquat
  • sethoxydim
  • trifluralin

Turf areas

  • No products approved for use in turf.

Bare ground areas

  • glyphosate
  • products containing diquat

Additional Images