Description:
This
annual plant has stems 6-10" long that are ascending or
sprawling. These stems are round, dark purple, and finely pubescent.
Multiple stems are produced from the base of the plant, otherwise they
are little branched. The opposite leaves are widely spaced along the
stems. Each leaf is about ¼" long and a little less across. It is
ovate, smooth along the margins, and slightly ciliate. The upper stems
terminate in small clusters of flowers; these flowers bloom only one or
two at a time on pedicels about ¼" long. Each flower is about 1/5" (4
mm.)
across, consisting of 5 white petals, 5 green sepals, 10 stamens, and 3
styles. The petals are unnotched at their tips, while the sepals are
lanceolate, slightly pubescent, and longer than the petals. The
blooming period occurs during late spring to early summer and lasts
about 1-2 months. The seed capsules are ovoid, the same length or a
little shorter than the sepals, and firm in texture. Each capsule has 3
bifurcated teeth (appearing to be 6 small teeth) along its upper rim.
It contains several seeds with pebbly
surfaces that are gray-black
and reniform. The root system consists of a taproot. This plant
reproduces by reseeding itself.
Cultivation:
Full sun, mesic to dry conditions, and poor soil are preferred. While
this plant can grow in more fertile soil, it has trouble competing with
taller, more aggressive plants.
Range & Habitat:
The adventive Thyme-Leaved Sandwort is a fairly common plant that
occurs in many
counties of Illinois, except for the NW and south-central areas of the
state (see Distribution
Map). It is native to Europe. Habitats include rocky glades,
cliffs, fields, cracks in sidewalks and along curbs, barren areas along
railroads and roadsides, and sunny waste areas that are gravelly or
sandy. This plant prefers disturbed habitats with scant vegetation; in
Illinois, it continues to spread into new areas.
Faunal Associations:
The small white flowers probably attract Syrphid flies and small bees.
The relation of this species to birds and mammalian herbivores is not
well understood.
Photographic Location:
Several plants were growing from the cracks of a sidewalk curb in
Urbana, Illinois.
Comments:
Thyme-Leaved Sandwort is a fairly common little plant that grows in
obscure corners of the landscape. Because of its small stature and
nondescript appearance, it is frequently overlooked by passersby. What
distinguishes Thyme-Leaved Sandwort from the similar-appearing Stellaria
and Cerastium spp. (Chickweeds) is the structure of
their flowers: the Chickweeds have petals that are notched at their
tips, unlike the petals of the former. The other Sandworts that occur
in Illinois have been reassigned to the Minuartia
genus and the Moehringia genus. These Sandworts
also have unnotched white petals, but their leaves are either smaller
in size or linear in shape. Many of these species have flowers that are
slightly larger and showier than those of Thyme-Leaved Sandwort.