Cerastium semidecandrum

Linnaeus

Sp. Pl. 1: 438. 1753.

Common names: Five-stamen mouse-ear chickweed
Introduced
Treatment appears in FNA Volume 5. Treatment on page 90. Mentioned on page 75, 83, 89.
Revision as of 23:31, 27 May 2020 by imported>Volume Importer

Plants annual, with slender taproot. Stems erect or ascending, branching at base, 1–20 cm, viscid, covered with short, dense, glandular and eglandular hairs; short axillary tufts of leaves absent. Leaves not marcescent, sessile but proximal leaves often spatulate; blade 5–18 × 2–5 mm, covered with short, white hairs; basal leaves with blade narrowly oblanceolate and ± spatulate, apex obtuse; cauline with blades ovate to elliptic-oblong, apex obtuse to acute. Inflorescences open, 3–30-flowered cymes; bracts lanceolate, with broad, scarious margins, glandular-pubescent. Pedicels curved at apex, often sharply angled at base, 3–8(–12) mm, 1–3 times as long as capsule, densely glandular-pubescent and viscid. Flowers: sepals narrowly lanceolate, 3–5 mm, margins broad, apex acute, glandular-pubescent; petals with unbranched veins, oblanceolate, 2–3 mm, shorter than sepals, apex notched; stamens 5; styles 5. Capsules cylindric, slightly curved, 4.5–6.5 mm, 1.5–2 times as long as sepals; teeth 10, erect, margins convolute. Seeds pale yellowish brown, 0.4–0.6 mm, finely tuberculate; testa not inflated. 2n = 36.


Phenology: Flowering spring.
Habitat: Common weed in dry, sandy, and gravelly places, roadsides and footpaths, parking lots, dunes
Elevation: 0-300 m

Distribution

V5 186-distribution-map.gif

Introduced; B.C., N.S., Ont., Ark., Conn., Fla., Ga., Idaho, Ill., Ind., Kans., La., Md., Mass., Mich., Mo., Nebr., N.J., N.Y., N.C., Ohio, Oreg., Pa., R.I., S.C., Wash., Wis., Eurasia.

Discussion

The very broad, scarious margins of the sepals and bracts distinguish this small, ephemeral species.

Selected References

None.

Lower Taxa

None.
... more about "Cerastium semidecandrum"
John K. Morton +
Linnaeus +
Five-stamen mouse-ear chickweed +
B.C. +, N.S. +, Ont. +, Ark. +, Conn. +, Fla. +, Ga. +, Idaho +, Ill. +, Ind. +, Kans. +, La. +, Md. +, Mass. +, Mich. +, Mo. +, Nebr. +, N.J. +, N.Y. +, N.C. +, Ohio +, Oreg. +, Pa. +, R.I. +, S.C. +, Wash. +, Wis. +  and Eurasia. +
0-300 m +
Common weed in dry, sandy, and gravelly places, roadsides and footpaths, parking lots, dunes +
Flowering spring. +
Introduced +
Cerastium semidecandrum +
Cerastium +
species +