Barnyardgrass (Echinochloa crus-galli)

Synonyms: Panicum crus-galli, Milium crus-galli, Orthopogon crus-galli

Common Names: Cockspur grass, barnyard millet, water grass, common barnyard grass

Description:

Barnyardgrass (Echinochloa crus-galli) is a fast-growing annual grass from Europe, Asia, and Africa that now grows throughout North America [1][4]. It is one of the most common weeds of gardens, fields, and damp, disturbed ground, where it sprouts from seed each year, grows quickly, and produces huge numbers of seeds [2][3]. MISIN tracks it because it competes strongly with crops and garden plants and turns up fast wherever soil is bare and moist [2].

Habit:

Barnyardgrass is a coarse summer annual grass that grows in clumps from 2 to 5 feet tall, sometimes taller [2]. Its leaf blades are flat, smooth, and rough-edged with a pale midrib, and the lower stems are often tinged reddish-purple near the base [2][3]. The single most useful identification feature is what it lacks: where the leaf wraps the stem, there is no ligule ? the small membrane or hair fringe most grasses have at that joint ? and no ear-like flaps (auricles) either [3]. It is easiest to identify from mid-summer into early fall, when it produces its seedhead: a coarse, branched cluster, green to purplish, that nods at the top, with the spikelets sometimes tipped by stiff bristles (awns) [2][3].

At-a-glance cues:

1. No ligule or auricles where the leaf meets the stem ? unusual among grasses [3]
2. Coarse summer grass, 2 to 5 feet tall, growing in clumps [2]
3. Lower stems often tinged reddish-purple at the base [2][3]
4. Branched, nodding, green-to-purplish seedhead in mid- to late summer, spikelets sometimes with stiff bristles [2][3]

Leaves:

1. Blades: flat, smooth (hairless), with rough edges and a pale midrib; up to about 20 inches (50 cm) long and 1/4 to 1/2 inch (1 to 2 cm) wide [2][3]
2. Ligule: absent ? no membrane or hair fringe where the blade meets the sheath; this is a key identification feature [3]
3. Auricles: absent (no ear-like flaps at the leaf base) [3]
4. Sheaths: smooth, the lower ones often reddish [2]

Stems:

1. Habit: erect to sprawling summer annual grass, about 2 to 5 feet (0.6 to 1.5 m) tall [2]
2. Texture: rather thick and smooth, branching near the base [2]
3. Color: often tinged reddish-purple toward the base [2][3]

Flowers:

1. Seedhead: a coarse, densely branched cluster (panicle), about 4 to 12 inches long, erect to nodding [2]
2. Color: green to purplish [2][3]
3. Spikelets: crowded along the branches; stiff bristle-like awns may or may not be present [3]
4. Seed-set time: about July through September or October [2][3]

Fruit and seeds:

1. Fruit: a small grain (caryopsis) about 1 to 2 mm long, oval, tan to brown [2][3]
2. A single plant can produce thousands of seeds [3]
3. Dispersal: seeds move in soil and water and as hitchhikers on mowing equipment, tools, shoes, and animals [3]
4. Seeds carry over in the soil and sprout in spring and early summer once the soil warms [3]

Habitat:

Barnyardgrass is native to Europe, Asia, and Africa [1]. In North America it is not native and now grows throughout the continental United States [4]. It thrives in open, sunny, disturbed ground with moist soil ? gardens, crop fields, roadsides, ditches, and the muddy edges of ponds, streams, and wetlands [2]. It tolerates wet conditions well and often shows up on exposed shores and riverbanks and in low, damp spots [2].

Reproduction:

Barnyardgrass spreads only by seed [2]. A single plant can make thousands of seeds, and they move easily ? in soil and runoff water, and as hitchhikers on mowing equipment, tools, boots, and animals ? so it appears quickly wherever the ground is bare and damp [3]. The seeds drop into the soil and can wait there before sprouting, mostly in spring and early summer once the soil warms [3]. Plants grow fast through the summer, flower and set seed from about July into fall, then die with the first frost [3].

For control timing: pull, hoe, or cut the plants before the seedheads ripen in mid- to late summer, so they cannot add seed to the soil [2][3].

Impact and Damage:

Barnyardgrass is mainly an agricultural and garden weed rather than a health hazard. It grows fast and competes strongly with crops and garden plants for water, nutrients, light, and space, and it is one of the most common and troublesome weeds of cultivated ground [2]. In a yard or garden it crowds vegetable beds, new plantings, and thin lawns, especially in damp spots [2][3].

In natural areas it colonizes bare, moist ground ? pond and stream edges, ditches, mudflats, and disturbed wetlands ? where it can form thick stands that crowd other low plants on open shores [2]. Because it favors disturbed, damp ground, heavy stands often signal recently bared or churned-up soil [2].

Similar species:

Barnyardgrass is one of the few common grasses with no ligule, which separates it from most look-alikes once you check where the leaf meets the stem.

Large crabgrass (Digitaria sanguinalis) is a common summer annual grass of lawns and gardens. Unlike barnyardgrass, it has a clear ligule and hairy leaves and sheaths, and it sprawls and roots at the lower joints rather than standing in a coarse clump [2][3].

Stinkgrass (Eragrostis cilianensis) is a smaller annual grass with fine, open, airy seedheads and a strong smell when crushed; barnyardgrass is much coarser and taller, with thick, branched seedheads [2].

Bermudagrass (Cynodon dactylon) is a low, creeping perennial that spreads by above- and below-ground runners and has finger-like seed spikes, while barnyardgrass is an upright annual that spreads only by seed [2].

Monitoring and rapid response:

Signs to watch for:

1. Coarse summer grass in clumps, 2 to 5 feet tall, on damp, disturbed, or bare ground [2]
2. Leaf joints with no ligule, and lower stems tinged reddish-purple [2][3]
3. Branched, nodding, green-to-purplish seedheads from mid-summer into fall [2][3]

What you can do:

1. Because it is an annual that spreads only by seed, the goal is to stop seed: pull or hoe young plants while the soil is moist, before the seedheads form [2][3]
2. Mow or cut plants before the seedheads ripen to keep them from seeding, and repeat as needed through the season [2]
3. Mulch bare, damp ground in beds to keep seedlings from sprouting [2]
4. Bag and trash mature seedheads rather than composting them, since the seed survives [3]
5. Natural area crews can pull or cut outlying plants along shores and ditches before seed set and revisit for a few seasons, since seed carries over in the soil [2][3]

When to call a professional:

1. Large or repeated infestations across cropland, shorelines, or other big areas where hand methods cannot keep up [2]
2. For chemical control options, contact a licensed applicator or your local cooperative extension office.

Report sightings to MISIN. Help track this species' spread by submitting observations through the MISIN web site or the MISIN mobile app (Android, iOS, Windows, and macOS). Photos at multiple angles paired with a precise GPS location are the most valuable data for confirming new occurrences and triggering rapid-response review.

Credits:

1. Plants of the World Online (POWO), Royal Botanic Gardens, Kew. Echinochloa crus-galli (L.) P.Beauv. powo.science.kew.org
2. Michigan State University Extension, Plant & Pest Diagnostics. Barnyardgrass ? Echinochloa crus-galli. canr.msu.edu
3. Penn State Extension. Lawn and Turfgrass Weeds: Barnyardgrass [Echinochloa crus-galli (L.) Beauv.]. extension.psu.edu
4. USDA NRCS PLANTS Database. Echinochloa crus-galli (L.) P.Beauv. plants.usda.gov

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