field mouse-ear chickweed

Field mouse-ear chickweed is a common, native, forb. It occurs throughout the United States and southern Canada north to Alaska, but it is mostly absent from the deep south, the Great Plains, and the Great Basin. It is found in high quality natural areas, including in prairies, woodland openings, and tundra, and on lake shores and dunes. It is also found in man-made or disturbed (anthropogenic) habitats, including meadows, fields, and roadsides. It grows under full or partial sun, in moist to dry, sandy, rocky, or gravelly soil.

Field mouse-ear chickweed is a 2″ to 12″ (5 to 30 cm) tall, perennial forb. At first, it has a vertical primary root (taproot) and forms a clump. Later, it develops a long-creeping system of tangled, short, underground, horizontal stems (rhizomes), and it forms a mat.

In the first year, it does not flower. In the early spring of the second year, it first has the appearance of a mat, with non-flowering stems laying on the ground, just their tips curving upward (decumbent). Later in the spring, one or more flowering stems appear. Flowering stems are mostly 2″ to 8″ (5 to 20 cm) tall, sometimes up to 11¾″ (30 cm) tall, and they are erect or they curve upward at the base (ascending). They are round, green or straw colored, and usually branched near the top. The pubescence is variable, from densely hairy to entirely hairless. They are often densely covered with spreading to downward-bent, non-glandular hairs, mixed with gland-tipped hairs at the middle of the stem, with the glandular hairs becoming more dense toward the top.

The leaves are opposite, stalkless, 1⁄16″ to 1″ (2 to 25 mm) long, and 1⁄32″ to 3⁄16″ (1 to 5 mm) wide. The leaf blades are linear to narrowly lance-shaped or inversely lance-shaped. They are usually sharply pointed but sometimes blunt at the tip. The midvein is conspicuously depressed on the upper surface. The upper and lower surfaces are usually hairy. The margins are untoothed. There is often a small tuft of shorter, narrower leaves rising from lower leaf axils.

The inflorescence is a cluster or an open, branched arrangement (panicle) of up to 20 flowers. At the base of each inflorescence there is a pair of modified leaves (bracts). The bracts have thin, white to translucent margins, but they are otherwise similar to the leaves. Each flower is on a stalk (pedicel) that is ⅜″ to ⅝″ (10 to 17 mm) long, about 2 times as long as the outer floral leaves (sepals). The pedicel is curved just below the base of the flower, and it is densely covered with both glandular and non-glandular hairs.

Each flower is about ½″ (12 mm) in diameter. There are 5 sepals, 5 petals, 10 stamens, and 5 styles. The sepals are green, narrowly elliptic, ⅛″ to ¼″ (3.5 to 6 mm) long, and tapered or angled to a sharp tip. They are covered with both glandular and non-glandular hairs. The petals are white, inversely egg-shaped, and ¼″ to ⅜″ (7.5 to 9 mm) long, about twice as long as the sepals. Each petal is deeply two-lobed at the tip and has distinct, translucent veins radiating from the base. The stamens have pale yellow anthers. Their stalks (filaments) are free, not fused together.

The fruit is a slightly curved, narrowly cylinder-shaped, 5⁄16″ to 7⁄16″ (7.5 to 11 mm) long, 1⁄16″ to ⅛″ (2.5 to 4 mm) wide, seed capsule. It contains 15 to 30 or more kidney-shaped seeds.

2″ to 8″ (5 to 20 cm)

White

Field chickweed (Cerastium arvense ssp. arvense)

Mouse-ear chickweed (Cerastium fontanum ssp. vulgare)

Moist to dry. Full or partial sun. Prairies, woodland openings, tundra, lake shores, dunes, meadows, fields, and roadsides. Sandy, rocky, or gravelly soil.

Spring

Sources

2, 3, 4, 5, 7, 24, 28, 29, 30.

Native

Common and widespread

Field Chickweed and a Prairie Violet...

This is another Field Chickweed I seen and a Prairie Violet.

Cerastium arvense: Field Chickweed or Field Mouse-Ear - Acker-Hornkraut
Inkor Pank

Field mouse-ear (Cerastium arvense) - 2017-04-08
Westdelta

Location: Norman Co. Mn.

Dan W. Andree
May 2024

Location: A prairie in Norman Co. Mn.

This is another Field Chickweed I seen and a Prairie Violet.