Foxtail Barley

What is foxtail barley?

Foxtail barley is a native, short-lived perennial bunchgrass that grows in the cool part of the season across most of the country. foxtail barley identification is easiest in early summer: look for dense clumps topped with nodding, feathery seed heads made of very long, fine bristles that shimmer green, red and purple before fading to tan. It is sometimes called wild barley, and it is not one of the green or yellow foxtail grasses, which are non-native summer annuals.

Those showy heads are the problem. Once seeds form, the barbed awns lodge in the mouths, eyes, noses and skin of grazing animals and can keep working deeper, leading to abscesses and infections. Livestock avoid mature plants, so foxtail barley increases as better grasses are grazed down, and it can take over wet, salty pastures and hay meadows in nearly pure stands. Hay that contains it is hard to use safely because animals can't sort out the awns.

Foxtail Barley identification: what to look for

Check low, damp or salty parts of a pasture, yard edge or roadside in June and July, when the heads are fully out. Up close, look at the collar where the leaf meets the stem and at the length of the bristles.

• Growth form: Dense tufts without creeping rhizomes, usually 1 to 2 feet tall.
• Leaves: Flat, gray-green to blue-green blades, sometimes hairy, about 1 to 6 inches long and no more than roughly 1/3 inch wide.
• Collar: A short, membranous ligule and no auricles, or only tiny ones.
• Seed head: A dense, nodding spike 2 1/2 to 4 inches long that looks silky and is tinted reddish or purple when fresh.
• Awns: Very long and hair-thin, roughly 1 to 2 1/4 inches, with tiny barbs that point backward and help them work into skin and fur.
• Mature heads: Fade to tan and turn brittle by mid to late summer, when the awned seeds catch in fur and wool.

Where it grows in the United States

Foxtail barley is native to western North America and now grows across most of the United States, except the southern Atlantic and Gulf Coast states. In California it occurs statewide up to nearly 10,000 feet. As a cool-season grass it starts growing in April or May and finishes its seed by midsummer, with plants at lower, warmer elevations seeding earlier than those higher up.

Water is the common thread. It is most at home in seasonally ponded ground, wet meadows, ditch and stream edges and the margins of sloughs and salt marshes, and it tolerates saline and alkaline soils that hold back many other grasses. It quickly claims ground exposed as water tables drop, and it thrives in overgrazed or poorly managed pastures and hay meadows.

Foxtail Barley look-alikes

A few plants get mixed up with it:

• Hare barley (Hordeum murinum ssp. leporinum): A related barley with a similar bristly head. Check the leaf collar: hare barley has distinct auricles, while foxtail barley's are missing or barely there.
• Green foxtail (Setaria spp.): Green, yellow and bristly foxtails are unrelated, non-native summer annuals that die each year. Foxtail barley is a native perennial that comes back from the same clump, and its heads carry 1- to 2-inch silky awns.

How to get rid of foxtail barley

Pulling, digging and mowing: Small patches can be dug or pulled before the heads form. Mowing or heavy grazing early in the season, before seed heads develop, cuts seed production, but the plants regrow and flower again, so repeat it. On cropland, fall plowing followed by spring harrowing usually controls established stands, while spring tillage alone does much less. Don't cut infested areas for hay once heads are out, and don't feed, sell or move contaminated hay, since even unfed bales can spread the seed.

Cultural control matters most, because the right conditions keep it from coming back.

• Fix the water. Where you control irrigation, reducing saturated soil before June slows it down, and draining low spots that pond in spring removes its favorite seedbed.
• Graze for the grass you want. Proper, rotational grazing keeps desirable grasses thick, while heavy, continuous grazing hands the pasture to foxtail barley.
• Graze or mow early in spring while the plant is still safe and palatable, before seed heads appear.
• After removing a stand, reseed with a more desirable grass so bare ground doesn't refill with foxtail barley.
• Late-spring burns during active growth damage it more than other burn timings, but results are mixed; work with a prescribed fire professional and follow local burn rules.

Herbicides: Spot-treating small clumps with glyphosate works, but it kills any plant it touches, including the grass around it. For larger stands, UC weed scientists list clethodim, a grass-selective herbicide, applied while plants are growing quickly at about 2 to 6 inches tall, and imazapic, where splitting the treatment between May and late June improved control; imazapic is not registered in California. Nebraska Extension lists imazapic for tolerant grass hay, pasture and rangeland, and glyphosate in tolerant alfalfa, clethodim, hexazinone or pronamide for alfalfa. Success drops sharply once seed heads are out, so spray in spring. Use only products labeled for your site, follow the label exactly including grazing and haying restrictions, and remember the label is the law. If you hire someone to spray, make sure they hold your state’s pesticide applicator license; the rules for each state are in our pesticide applicator license guide.

Keeping it from coming back

Foxtail barley thrives where better grasses are weak and the ground stays wet. Keeping well-established perennial grasses and forbs in place, grazing rotationally and managing drainage are the cheapest long-term defenses.

Scout in April and May so new patches are caught before they seed, and don't buy or move hay that contains its heads. Seed can live in the soil for several years, up to about seven by some estimates, so plan on a few seasons of follow-up after any cleanup.

Questions we get about foxtail barley

Similar weeds

Green FoxtailSetaria viridisBuffaloburSolanum rostratumCommon TansyTanacetum vulgare