Cerastium fontanum Baumg.
mouse-ear chickweed
Perennial, often with short tufted non-flowering axillary branches. Flowering stems ascending to erect, (5)-15-45-(60) cm tall, with dense spreading eglandular hairs. Lvs ovate, lanceolate, elliptic or oblanceolate, (5)-10-25-(50) × 3-10-(20) mm, the lower petiolate, the upper sessile, with eglandular hairs. Infl. crowded; infructescence lax; fruiting pedicels usually > sepals, with dense eglandular hairs. Bracts ovate, the lower without scarious margins, eglandular hairy on both surfaces, the upper with scarious margins, glabrous above. Sepals scarious on margins, 4-6 mm long, glabrous above, with eglandular hairs on green part beneath; hairs not overtopping apex. Petals c. = sepals. Styles 1.5-2 mm long. Capsule cylindric, 2× length of calyx. Seeds c. 0.6 mm long, tuberculate.
N.; S.; St.; K., Ch., A., C.: throughout.
N. temperate 1855
Tussock grassland and pasture, waste places, roadsides, riverbeds, swamps, scrub, shingle slides, lake shores, sand dunes, stream banks.
FL (Aug)-Oct-Mar-(Jun) FT (Sep)-Nov-Apr-(Jun).
Mouse-ear chickweed can be distinguished from the other small-flowered Cerastium spp. by the absence of glandular hairs on the sepals, the sepal hairs not overtopping the sepal apex, and the styles 1.5-2 mm long.
N.Z. material of C. fontanum belongs to subsp. vulgare (Hartman) Greuter et Burdet. Following changes made to the International Code of Botanical Nomenclature at the 13th International Botanical Congress in 1981, that name replaces C. fontanum subsp. triviale by which name mouse-ear chickweed was formerly known (e.g., Garnock-Jones 1981). The sp. has also been known as C. holosteoides, C. triviale and C. vulgatum in N.Z. C. amblyodontum Colenso and C. truncatulum Colenso, originally treated as native spp., are based on specimens of C. fontanum subsp. vulgare.
