Classification Hierarchy
Kingdom Plantae
Subkingdom Tracheophyta
Superdivision Spermatophyta
Division Magnoliophyta
Class Magnoliopsida
Subclass Caryophyllidae
Order Caryophyllales
Family Caryophyllaceae
Genus Myosoton
Species Myosoton aquaticum
Giant chickweed

Date: september 21, 2010. Location: Hickory Hill (map)

USDA Plant Profile Flora of N. America

Scientific Name: Myosoton aquaticum

Common Name: Giant chickweed, Water chickweed

Origin: Alien

Notes: Several genera contain species called Chickweed. Stellaria species have three styles. Myosoton and Cerastium species usually have five styles. The bifid flower petals are most deeply cleaved in Myosoton aquaticum (Giant chickweed) and Stellaria meadia (Common chickweed). Other Stellaria and Cerastium species are usually notched no deeper than half the petal length.

Additional references: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15.

Field Marks for Identification:

Flowers: May, small, white - petals, sepals, styles in fives. The five deeply divided petals appear to be ten, ten anthers.

Leaves: opposite, ovate, most cauline leaves sessile; however, the lowest leaves on the stem may be petiolate.

Stems: terete to angular (square-ish)

Glossaries of botanical terms: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.

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