Stellaria neglecta
Encyclopedia
Stellaria neglecta, greater chickweed, is an annual
Annual plant
An annual plant is a plant that usually germinates, flowers, and dies in a year or season. True annuals will only live longer than a year if they are prevented from setting seed...

 or short-lived perennial herbaceous
Herbaceous
A herbaceous plant is a plant that has leaves and stems that die down at the end of the growing season to the soil level. They have no persistent woody stem above ground...

 plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...

 in the family Caryophyllaceae
Caryophyllaceae
The Caryophyllaceae, commonly called the pink family or carnation family, is a family of flowering plants. It is included in the dicotyledon order Caryophyllales in the APG III system, alongside 33 other families, including Amaranthaceae, Cactaceae and Polygonaceae...

. It is native to Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

 and has been introduced to North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

.

Taxonomy

Stellaria neglecta forms part of a complex that also includes S. media and S. pallida
Stellaria pallida
Stellaria pallida, commonly known as lesser chickweed, is an annual herbaceous plant in the family Caryophyllaceae. It is native to Europe and is an introduced species in North America.-Taxonomy:...

. The last of these is generally separable on morphological grounds, but there is no clear-cut morphological distinction between S. neglecta and S. media, which are easily confused; neglecta was formerly treated as a subspecies of S. media.

Description

Stellaria neglecta resembles S. media, but is generally larger in all its parts. It has weak branching stems, that are usually decumbent at the base, ascending distally to around 80–90 cm. Between each pair of nodes, the stem carries a single row of hairs. The lower leaves are long-stalked, with the leaf blade 1-2.5 cm long and the stalk up to twice as long; the upper leaves have a short flattened stalk or are sessile
Sessility (botany)
In botany, sessility is a characteristic of plants whose flowers or leaves are borne directly from the stem or peduncle, and thus lack a petiole or pedicel...

, with the leaf blade up to 5 cm long; the leaf blade is ovate to broadly elliptical, acuminate, and glabrous.

Flowers are borne on long slender stalks which are glabrous or pubescent, initially spreading and reflexed, later erect. There are five sepals, 5-6.5 mm long, lanceolate, glabrous or pubescent, with an acute apex. The five petals are white, deeply bifid, the cleft extending almost to the base and giving the impression that there are actually ten petals; in length the petals are equal to or slightly longer than the sepals. The flowers are about 10 mm in diameter. There are usually 10 stamens and three styles.

S. neglecta flowers between April and July, after which the flowering parts decay. The stems remain alive and produce tiller
Tiller
A tiller or till is a lever attached to a rudder post or rudder stock of a boat that provides leverage for the helmsman to turn the rudder...

s which overwinter and flower the following year.

Seeds are tuberculate
Tubercle
A tubercle is generally a wart-like projection, but it has slightly different meaning depending on which family of plants or animals it is used to refer to....

, dark reddish-brown, 1.3-1.7 mm in diameter. The tubercles are conical , with an acute apex.

Distribution

Greater chickweed is widely distributed throughout Europe, from the Mediterranean to the Baltic
Baltic region
The terms Baltic region, Baltic Rim countries, and Baltic Rim refer to slightly different combinations of countries in the general area surrounding the Baltic Sea.- Etymology :...

 and Scandinavia
Scandinavia
Scandinavia is a cultural, historical and ethno-linguistic region in northern Europe that includes the three kingdoms of Denmark, Norway and Sweden, characterized by their common ethno-cultural heritage and language. Modern Norway and Sweden proper are situated on the Scandinavian Peninsula,...

, and from the British Isles
British Isles
The British Isles are a group of islands off the northwest coast of continental Europe that include the islands of Great Britain and Ireland and over six thousand smaller isles. There are two sovereign states located on the islands: the United Kingdom of Great Britain and Northern Ireland and...

 to the Ukraine
Ukraine
Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...

, but is nowhere common. In Great Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...

, it is most common in the south and west, infrequent in the north. In North America, it was formerly rare, but it has spread rapdly in recent decades and is now considered a weed in a number of states, from Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...

 to California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

.

Habitat

S. neglecta prefers damp, shady conditions, and is usually found in woodland, hedges or on the banks of streams.

Similar species

Separation of S. neglecta from S. media on morphological grounds alone is difficult. In Britain, Whitehead and Sinha found that specimens with ten perfect stamens, petals more or less equalling the sepals, and growing on the margins of streams, lakes or other damp places, were assignable to S. neglecta. While S. neglecta usually has ten stamens, S. media may have as few as 3-7. Other differences are that S. neglecta is invariably found as a ruderal in damp conditions, while S. media also occurs as a weed, in a variety of habitats, including cultivated ground; and S. neglecta flowers only between April and July, while S. media flowers throughout the year.
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