Description:
This herbaceous perennial plant is 3–10" tall, forming leafy stems that
often branch near the base. During the early stages of development in
the spring, the foliage often has a matted appearance. Individual stems
are light green, terete, and pubescent (sometimes becoming
glandular-pubescent above). Pairs of opposite leaves occur along these
stems; there are more pairs of leaves below than above. These leaves
are usually ascending and slightly recurved. Individual leaves are ¼–1¼"
(6–30 mm.) long and 1.5–6 mm. (up to ¼") across; they are narrowly
lanceolate to lanceolate, narrowly oblanceolate, or linear-oblong in shape with margins
that are toothless and ciliate. These leaves are sessile or they
slightly clasp the stems. The upper and lower leaf surfaces are medium
green and usually sparsely pubescent; there tends to be more hairs
along the lower side of the central vein of the leaves and along the
margins. Small tufts of secondary leaves often develop from the axils
of the lower leaves; these secondary leaves are similar to the primary
leaves, except they are shorter and more narrow. The upper stems
terminate in cymes or flat-headed panicles of flowers; usually only a
few flowers are in bloom at the same time in each inflorescence.
Individual flowers span about 1/3" (8 mm.) across (sometimes slightly
more), consisting of 5 white petals, 5 light green sepals, 10 stamens
with pale yellow anthers, and a yellowish green pistil with 5 styles.
On uncommon occasions, a flower will have 4 petals, 4 sepals, and 8
stamens.
Individual petals are ascending and recurved; they are
narrowly obcordate in shape with 2 rounded lobes (uncommonly with 3
rounded lobes) and there are fine translucent veins that radiate from
the center of the flower. These veins are primarily straight, although
they branch occasionally. The sepals are lanceolate in shape and
pubescent to glandular-pubescent; they are about one-half to two-thirds of the length
of the petals. At the base of each inflorescence, there is a pair of
small leafy bracts that are lanceolate to ovate in shape; they are
similar to the leaves. The branches of the inflorescence and the
pedicels of the flowers are similar to the stems, except they are more
likely to be glandular-pubescent. Individual pedicels are ¼–1¼" (6-30
mm.) long. The blooming period occurs from mid- to late-spring, lasting
about 1 month. Afterwards, the flowers are replaced by seed capsules.
These seed capsules are about 8–11 mm. (1/3" or slightly more) in
length, narrowly cylindrical in shape, and usually curved slightly to
one side. At the apex of each capsule, there are 10 tiny teeth. The
capsules become light tan at maturity, at which time the flowering
leafy stems die down. Each capsule contains several tiny seeds.
Individual seeds are 0.5–1.2 mm. across, somewhat flattened, and tuberculate across the surface. The
root system consists of a taproot, later
developing short-rhizomes.
Cultivation: The
preference is
full or partial sun, mesic to dry conditions, cool temperatures, and a
barren calcareous soil containing sand or rocky material. This plant
can also be cultivated in gardens in loamy soil. Most growth and
development occurs during the spring. Low leafy stems that are sterile
may persist during the summer, autumn, and winter if there is enough
moisture.
Range
&
Habitat: This subspecies of Field
Chickweed (Cerastium arvense strictum) is native to Illinois, occurring
as an occasional plant in NE Illinois and an uncommon plant in
scattered counties in the southern half of Illinois (see
Distribution
Map). It is widely distributed in North America, especially
in boreal
areas. Habitats include gravel hill prairies, sand prairies, sand
dunes, alvars (north of Illinois), openings in rocky upland woodlands,
sandstone and limestone cliffs, grassy meadows, and abandoned fields.
This plant is found in both higher quality natural areas and disturbed
areas.
Faunal Associations:
The nectar and pollen of the flowers
attract primarily bees, including little carpenter bees (Ceratina
spp.), cuckoo bees (Nomada spp.), mason bees (Osmia spp.), Halictid
bees (Lasioglossum spp.), and Andrenid bees (Andrena spp.); see Steury
et al. (2009). Some insects feed destructively on Field Chickweed and
other mouse-eared chickweeds (Cerastium spp.). This includes larvae of
such moths as
Haematopis
grataria (Chickweed Geometer),
Heliothis
borealis (Boreal Gem), and
Hadena capsularis (Capsule
Moth); the larvae
of these moths feed on the flowers and developing seeds (Natural
History Museum website, accessed 2010). Other insect feeders include
Melanoplus borealis (Boreal
Grasshopper) and
Aphis
sambuci (Elder
Aphid); see Wyoming Agr. Exp. Sta. (1994) and Blackman & Eastop
(2013). The seeds of chickweeds are eaten by many small rodents,
including the Deer Mouse, Meadow Jumping Mouse, House Mouse, and
Thirteen-lined Ground Squirrel (Houtcooper, 1978; Whitaker &
Mumford, 1970; Whitaker, 1972). The Field Sparrow and probably other
granivorous songbirds also eat the seeds occasionally (DeVore et al.,
2004).
Discussion: Field
Chickweed is the most attractive
mouse-eared chickweed in Illinois (Cerastium) because it has the
largest flowers.
Being a perennial plant, rather than an annual plant (like most
chickweeds), it is also easier to sustain in the garden. Field
Chickweed (Cerastium arvense) has a history of taxonomic instability
because of its variable characteristics across its range in North
America and Europe. Two other subspecies of Field Chickweed include
Cerastium arvense
arvense (native to Europe, introduced into North
America) and
Cerastium
arvense velutinum (native to North America,
including Illinois). These latter two subspecies can be distinguished
from
Cerastium arvense
strictum by their ranker growth (stems often
exceeding 10" in length), larger flowers (about ½" across), and long
rhizomes.