T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Stellaria media (Common Chickweed)

Kingdom: Plantae
(Unranked): Angiosperms
(Unranked): Eudicots
(Unranked): Core eudicots
Order: Caryophyllales
Family: Caryophyllaceae
Genus: Stellaria
Species: S. media
Binomial name: Stellaria media 
Common name: Common Chickweed, Chickenwort, Craches, Maruns, Winterweed.

Stellaria media is a cool-season annual plant native to Europe, which is often eaten by chickens. It is one of the most widespread and extremely resistant weeds, especially in tilled crops, occurs in kitchen gardens, orchards, along roadways, near habitation. Common Chickweed is very competitive with small grains and can produce up to 80% yield losses among barley.
Germination period is from early spring until first autumn frosts. Stellaria media yields 2-3 generations in a summer. The plant forms large mats of foliage.
The flowers (5-6mm broad) are white, small and star-like. It has 5 petals which are deeply notched and appears as having 10 petals (2mm long). The stamens typically 3-5, attached at the base of the ovary, alternating with petals. Styles 3, spreading. Sepals 5, free, to 5mm long, pubescent with glandular-tipped hairs, ovate-lanceolate, green.  This plant flowers and sets seed at the same time. Seeds are numerous, rounded or reniform, squeezed, brown. Seed germination depth is 1-2 cm. Seeds per plant: 15,000 (10,000-20,000). Seeds maintain their ability to germinate in the soil for 2-5 years. It propagates with rooted stems as well.
The stem is usually prostrate, 5-30 (40) cm long, round, one row of hairs, often twisting, developing roots at the nodes. If the stem is carefully bent side-to-side and then pulled apart, the elastic vascular tissue can be seen. This is a good way to help identify the plant.
The seed capsules are up to +6mm long, 4mm wide, glabrous, with +/-15 seeds. Seeds are 1mm in diameter, tuberculate, rotund.  Its root is thin and ramified.
The leaves are opposite, ovate (sometimes truncate at the base), short-mucronate, petiolate. Blades to +2cm wide, +2cm long, glabrous, green above, lighter green below. The petiole is +2cm long, sometimes winged, pubescent.

Stellaria media is edible and nutritious and is used as a leaf vegetable, often raw in salads.

The top surface of a leaf.

The underside of the leaves.

Thanks to Wikipedia for text and information http://creativecommons.org/licenses/by-sa/3.0/