(Photos: E.Cousins; chickweed growing with other weeds; close-up of one stem)
Chickweed grows in a wide variety of soil types and habitats. It definitely prefers cool, moist conditions so is mostly seen as a winter annual. The slender branched stems intertwine to produce a large mat of foliage, from 5-50 cm tall. The bright green plant is distinguishable by a line of fine hairs on one side of the stems only, between nodes. Leaves are oval in shape, with pointed tips. Lower leaves have no stalk (sessile) but upper ones do (petiolate). The small white flowers are star-shaped (as stellaria would suggest) with 5 petals, each just 3-4mm long. These grow from the tip of the plant, or from joints along the stem.
This weed can be used as a cooling herbal remedy, to ease itchy skin. It is also grown as a food for humans and poultry because of its nutritional value. The plant does contain toxins called saponins, which are poorly absorbed by humans and break down if thoroughly cooked; however they can be harmful to some creatures or if consumed in large quantities. Plants can normally be removed easily after rain by hand-pulling…then maybe feed it to your chickens!