mouseear chickweed (Cerastium fontanum ssp. vulgare)
Cerastium adsurgens Greene
Cerastium fontanum Baumg. ssp. holosteoides auct. non (Fr.) Salman,
van Ommering & de Voogd
Cerastium fontanum Baumg. ssp. triviale (Link) Jalas
Cerastium holosteoides auct. non Fr.
Cerastium holosteoides Fr. var. vulgare (Hartm.) Hyl.
Cerastium triviale Link
Cerastium vulgatum L. 1762, non 1755
Cerastium vulgatum L. var. hirsutum Fr.
Cerastium vulgatum L. var. holosteoides auct. non (Fr.) Wahlenb.
CONFIRMATION STATUS: Pending confirmation.
TAXONOMY: The currently accepted scientific name of mouse-ear
chickweed Cerastium fontanum. Most references to this plant simply
refer to it as Cerastium fontanum; however, there are two subspecies
recognized - subspecies fontanum and subspecies vulgare. Sub-
species fontanum is not naturally found in the United States or Can-
ada; subspecies vulgare is found throughout nearly all of North
America north of Mexico. References to Cerastium fontanum, there-
fore, can be assumed to refer to subspecies vulgare.
NATIVE STATUS: Introduced, United States and Canada.
GENERAL BOTANICAL CHARACTERISTICS:
Habit: This introduced perennial plant is tufted at the base, producing
multiple stems up to 1½' long, although they are usually about one-half
of this length or less. These stems are ascending to widely spreading;
they are green or purple, terete (round in cross-section), and pubescent.
Leaves: The opposite leaves are up to 1" long and 1/3" across (or a little
larger); they are variably shaped, including lanceolate-ovate, oval-oblong,
or broadly oblanceolate. The leaves are pubescent, smooth along the mar-
gins, and sessile at the base; they have a prominent central vein on the
Flowers: The stems often terminate in small cymes (flat-headed clusters)
of 1-5 small flowers; both the peduncles and pedicels of these cymes are pubescent. At the base of each cyme, there is a pair of leafy bracts with
thin translucent margins. Each flower is up to ¼" across, consisting of 5
green sepals, 5 white petals with notched tips, 10 stamens with pale yel-
low anthers, and 5 styles; some plants may produce flowers with fewer
than 10 stamens. The sepals are lanceolate, pubescent, and translucent
along their margins; they are about the same length as the petals.
Fruit/Seeds: Each flower is replaced by a cylindrical seed capsule with
10 small teeth along its upper rim. Each seed capsule containing several
small seeds. The seeds are somewhat flattened and minutely warty or
Roots: The root system is mostly fibrous. This plant reproduces primarily
by reseeding itself; it can also form vegetative offsets when the nodes of
the lower stems develop rootlets while lying on moist ground.
REGENERATION PROCESS: Mouse-ear chickweed propogates itself
primarily by reseeding; it also spreads by vegetative offsets from rootlets.
HABITAT TYPES: Mouse-ear chickweed, introduced from Eurasia, is
quite common throughout North America. Habitats include fields, pastures,
lawns, gardens, roadsides, areas along railroads, areas adjacent to buildings, vacant lots, degraded grassy meadows, and waste areas. Areas with a his-
tory of disturbance provide preferred habitats. As human structures have
rapidly accelerated, common mouse-eared chick- weed has also rapidly
expanded its distaribution range.
SITE CHARACTERISTICS: The preference is full sun to light shade
and moist to slightly dry conditions. This plant can tolerate a broad range
of soils, including those that contain loam, clay-loam, and pebbly or
gravelly material. Common mouse-eared chickweed is more often found
in fertile soil than other Cerastium spp. (Mouse-Eared Chickweeds). It is
a larger plant that can tolerate more competition from other kinds of veg-
SEASONAL DEVELOPMENT: The blooming period occurs intermit-
tently from late spring to early fall and may last several months for
GENERAL DISTRIBUTION: Mouse-ear chickweed is distributed
throughout nearly all of the continental United States and Canada.
SKY MEADOWS DISTRIBUTION: To be determined.
IMPORTANCE AND USES: The flowers attract various bees and flies;
these insects suck nectar primarily, although some Syrphid flies feed on
the pollen and some of the smaller bees (e.g., Halictid bees) collect pollen
for their larvae. The caterpillars of several moths feed on the foliage of
Chickweeds (Cerastium spp., Stellaria spp.), including Agrostis vener-
abilis (venerable dart), Haematopis grataria (chickweed geometer), and
Lobocleta ossularia (drab brown wave). Sparrows and other small
granivorous songbirds eat the seeds of Chickweeds. Because common
mouse-eared chickweed is one of the larger chickweeds that grows
during the summer, the cottontail rabbit nibbles on its foliage occasion-
Crooked Run Valley