Smooth Crabgrass

Digitaria ischaemum

Smooth Crabgrass is a low, spreading grass which is common in fields, waste areas, and lawns.

This grass is light green in color when young, with parts turning reddish-purple as it ages.

Smooth Crabgrass grows as a rosette, meaning it is rooted in the center with leaves and stems spreading outwards. Leaves grow one to three inches long.

An older plant can grow up to about 15 inches tall, but usually they are much shorter.

Smooth Crabgrass was introduced in America from Europe.

Virginia Tech

Virginia Tech

Smooth Crabgrass flowers are tiny and have no petals. They grow on spikes rising straight up from the plant.

Flowers bloom from July to October.

The seeds of crabgrass are eaten by many animals, including Mourning Dove, Northern Bobwhite, Wild Turkey, Brown-headed Cowbird, Dark-eyed Junco, and sparrows. Eastern Cottontails eat the leaves.

Smooth Crabgrass is an annual, which means it dies after one year. Each summer, many crabgrass plants in the same area will spread together to make a mat.

While it will compete with, and choke out, other grasses, Smooth Crabgrass often grows alongside other "weed" plants, such as clover and plantain.

Animals that eat crabgrass seeds help spread the plant by pooping the seeds out in new places.

Relationships in Nature:

Animals Using as Food Source

Animals Using as Shelter

Associations With Other Plants

OTHER

Mourning Dove

Common Black Ground Beetle

Red Clover

Eastern Cottontail D

Wild Turkey

American Dog Tick

English Plantain

Mourning Dove D

Northern Bobwhite

White-breasted Nuthatch

Pokeweed

Wild Turkey D

Dark-eyed Junco

Mourning Dove

Smooth Sumac

Dark-eyed Junco D

Brown-headed Cowbird

Northern Ringneck Snake

Common Milkweed

Brown-headed Cowbird D

Eastern Cottontail

Great Crested Flycatcher

Queen Anne's Lace

Northern Bobwhite D

Field Cricket

American Goldfinch

Common Dandelion

American Goldfinch D

Northern Cardinal

Carolina Chickadee

Switchgrass

American Goldfinch

Eastern Bluebird

Devil's Beggar-tick

Canada Goose

Eastern Mole

Lamb's Quarters

Woodchuck

Northern Bobwhite

Common Ragweed

Differential Grasshopper

Differential Grasshopper

Jimsonweed

White-throated Sparrow

Northern Mockingbird

Bird-foot Violet

Tufted Titmouse

Chicory

Ring-legged Earwig

Bushy Aster

Common Grackle

Kentucky Bluegrass

Polyphemus Moth

Wild Strawberry

Six-spotted Tiger Beetle

Common Mullein

European Starling

Chigger

Relationship to Humans:

Most people who garden or care for lawns despise Smooth Crabgrass. It takes over from other grasses which are more desirable in lawns. It hardly ever gets mowed, because usually most of the plant is below the lawnmower blade. Along with dandelions, this is probably the most common weed pulled from gardens. On the other hand, Smooth Crabgrass will often grow in places where no other plants will grow, making them green and lush, as well as attracting wildlife.

SCIENTIFIC CLASSIFICATION

KINGDOM
Plant
DIVISION
Magnoliophyta
CLASS
Liliopsida
ORDER
Cyperales
FAMILY
Poaceae
GENUS
Digitaria
SPECIES
Digitaria ischaemum

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