common chickweed (Stellaria media)
SCIENTIFIC SYNONYMS: There are no scientific synonyms for
CONFIRMATION STATUS: Pending confirmation.
TAXONOMY: The currently accepted scientific name of common chick-
weed is Stellaria media (L.) Vill. This is probably the best known chick-
weed in North America, although it can be confused with other species.
The Chickweeds fall into 2 large groups: those with 3 styles (Stellaria spp.)
and those with 5 styles (Cerastium spp.). Like other Stellaria spp. (Chick-
weeds), common chickweed has only 3 styles. It differs from the others
in this genus by the large size of its sepals (at least 1/8" long), which are
conspicuously longer than the petals of the flowers. The foliage of common
chickweed resembles Stellaria pallida (apetalous chickweed) to a remark-
able degree; however, the flowers of apetalous chickweed lack petals and
their sepals are shorter. The blooming period of apetalous chickweed is
restricted to the spring, while common chickweed often blooms later in
the year. Common chickweed is somewhat variable in the hairiness of its
leaves, the length of its stems, and the number of stamens in each flower.
The PLANTS Database lists three subspecies for Stellaria media: 1) sub-
species media, 2) subspecies neglecta, and 3) subspecies pallida. Only
subspecies media and pallida are beleived to occur in Virginia. The Atlas
of Virginia Flora only lists Stellaria media without subspecies designation.
For the Nature Guide, subspecies media will be presumed.
NATIVE STATUS: Introduced, United States and Canada.
GENERAL BOTANICAL DESCRIPTION:
Habit: This adventive annual plant produces stems about ½–1' long that
usually sprawl across the ground. It branches abundantly near the base,
but very little toward the tips of the stems. The somewhat succulent stems
are green or burgundy; they often have lines of white hairs.
Leaves: Pairs of opposite leaves occur at intervals along these stems.
These leaves become larger toward the tips of the stems, spanning ½–1"
in length and ¼–½" across. The leaves toward the base of the plant usually
have short petioles that are slightly hairy, while the leaves near the tip of
each stem are usually sessile. Each leave is more or less ovate, smooth
along the margins, and hairless on the upper surface; the lower surface is occasionally hairy.
Flowers: Individual flowers occur from the axils of the outer pairs of
leaves, while the stems terminate in small cymes of white flowers. Each
flower is about ¼" across, consisting of 5 white bifid petals (appearing to
be 10 petals), 5 green sepals, 3 white styles, 2-10 stamens, and a green
ovary in the center. The sepals are lanceolate, hairy on the outer surface,
and longer than the petals; each sepal is at least 1/8" long (about 3-5 mm.).
The slender pedicels are finely pubescent. A typical plant will bloom sporadically for 1-2 months.
Fruit/Seeds: Each flower is replaced by a seed capsule that is light brown
with 6 small teeth along its upper rim; it contains several seeds. Each
mature seed is dark reddish brown, some- what flattened, and nearly orb-
icular; its surface has tiny pebbles.
Roots: The root system is shallow and fibrous. This plant spreads by re-
seeding itself; it can also spread vegetatively by rooting at the leaf nodes
along the stems.
REGENERATION PROCESS: Common chickweed propogates itself by
reseeding and by vegetative spreading through rooting at the leaf nodes.
HABITAT TYPES: Common chickweed is native to Eurasia. Habitats
include woodland areas prone to flooding, thickets, cropland and fallow
fields, lawns and gardens, nursery plots, areas adjacent to buildings, and miscellaneous waste areas. While this species occurs to a limited extent in natural habitats, it prefers areas with a history of disturbance.
SITE CHARACTERISTICS: Typical growing conditions for common chickweed consist of partial or full sun, moist to mesic conditions, and a
fairly fertile loam or clay-loam soil. Light shade and temporary flooding
SEASONAL DEVELOPMENT: The blooming period occurs during
the spring for plants that are winter annuals, and during the summer or
fall for plants that are summer annuals.
GENERAL DISTRIBUTION: Common chickweed is found throughout
the North American continent. It has been recorded in every state and prov-
ince in the United States and Canada (with the possible exception of some
the northern territories).
SKY MEADOWS DISTRIBUTION: To be determined.
IMPORTANCE AND USES: The nectar and pollen of the flowers at-
tract Andrenid bees, Halictid bees, and various kinds of flies, including
Syrphid flies, Muscid flies, flesh flies, and Anthomyiid flies. In the ab-
sence of such visitors, the flowers can self-pollinate. The caterpillars of
some moths feed on the foliage, including Agrotis venerabilis (venerable
dart), Haematopis grataria (chickweed geometer), Lobocleta ossularia
(drab brown wave). Small granivorous songbirds eat the seeds, while
chickens and possibly some upland gamebirds eat both the foliage and
seeds. Among mammalian herbivores, the cottontail rabbit and hogs eat
the foliage without apparent ill-effect.
Crooked Run Valley