This annual plant is 4-16" tall, usually forming a tuft of leafy stems
that are ascending to sprawling. These stems are branched at the base
near the crown of the plant, otherwise they are unbranched. Individual
stems are light green, terete, and glandular-hairy. Pairs of opposite
leaves occur along these stems (typically at intervals of 1-2½"). These
leaves are ¾-2" long, 5-9 mm. across, and elliptic,
oblong-lanceolate, or oblong-oblanceolate in shape. The leaf
margins are smooth (entire) and slightly ciliate. The leaf
surfaces are medium green and either sparsely short-pubescent
or hairless. Each leaf has a prominent central vein.
stems terminate in either cymes or compound cymes of flowers (usually
the latter); these cymes are dichotomously branched and variable in
size. Each terminal branch of the inflorescence typically has 3 flowers
with divergent slender pedicels up to 1¼" long. While the flower buds
are nodding, the flowers are more erect. Similar to the stems, the
branches and pedicels of each inflorescence are light green, terete,
and glandular-pubescent. At the base of each pair of branches in an
inflorescence, there is a pair of leafy bracts up to ¾" and 5
across. These bracts are lanceolate in shape and they lack membranous
margins. The flowers are up to ¼" across while they are in bloom. Each
flower has 5 white petals with notched tips, 5 green sepals, an ovary
with 5 styles, and 10 stamens (usually). The sepals are
in shape with membranous margins and short-pubescent; they are about
3-5 mm. long. The petals are the same length or a little longer than
the sepals. The blooming period occurs
from mid-spring to
summer, lasting about 1 month. Usually, only a few flowers are in bloom
at the same time. Sometimes cleistogamous flowers that fail to open are
Afterwards, the flowers are
replaced by cylindrical seed
capsules that become 8-12 mm. long at maturity. Like the flowerbuds,
they tend to nod downward. Mature seed capsules are
membranous, light tan, longitudinally veined, and often
slightly curved; they are more than twice as long as the sepals. Each
seed capsule has an open rim at its apex with 10 tiny teeth. Each seed
capsule contains several tiny seeds about 0.5 mm. in length. The seeds
are obovoid, somewhat flattened, brownish, and minutely tuberculate
(warty). The root system system consists of a shallow spreading taproot.
The preference is full sun to light shade and moist conditions. Nodding
Chickweed is not particular about soil. Most growth and development
occurs during the spring when the weather is cool and moist, after
which the foliage dies down.
Nodding Chickweed is occasional to locally common in most areas of
Illinois. Habitats include floodplain woodlands,
streambanks in wooded areas, ravines and ledges along streams, gravel
bars along rivers, weedy meadows, nursery plots, and moist waste areas.
Nodding Chickweed occurs in both natural areas and human-mediated
environments. In natural areas, it tends to occur in places where there
is some disturbance by the action of water (e.g., soil erosion or
deposits of gravel).
The flowers are
cross-pollinated by honeybees, Halictid bees (Halictus spp.
small butterflies, Syrphid flies, and other flies
(Robertson, 1928). Both nectar and pollen are available as floral
rewards. The caterpillars and cutworms of various moths are known to
feed on chickweeds (Stellaria
). These moth species
(Chickweed Geometer), Lobocleta ossularia
(Drab Brown Wave), Agrotis
(Venerable Dart), Hyles lineata
(White-Lined Sphinx), Feltia
(Dingy Cutworm), Xestia
(Spot-Sided Cutworm), and Xanthorhoe ferrugata
Twin-Spot). Vertebrate animals also feed on these plants to some
extent. Various sparrows and other granivorous songbirds eat the seeds,
while deer, rabbits, and domesticated farm animals (cattle, horses,
sheep, & pigs) occasionally browse on the foliage.
A gravel bar along a river in a wooded area of
Pine Hills State Nature Preserve in east-central Indiana.
Notwithstanding its weedy appearance and habits, this is one of the
native chickweeds in Illinois. It is a rather floppy plant with small
white flowers. Nodding Chickweed can be distinguished from other
) by the shape of its leaves,
diffuse inflorescence, and structure of its flowers. In particular, the
pedicels of its flowers are rather long (1" in length or more) and
divergent, while its flowerbuds and seed
capsules nod downward. Among the Mouse-Eared
Nodding Chickweed has rather long and narrow leaves.
Some authorities consider the more western Cerastium
to be a variety of Nodding Chickweed,
. This latter species (or variety) tends to
hairy leaves and its pedicels are shorter (less than 1" in length).