Common wood sorrel

Common wood sorrel
Scientific classification
Kingdom:	Plantae
Division:	Magnoliophyta
Class:	Magnoliopsida
Order:	Geraniales
Family:	Oxalidaceae
Genus:	Oxalis
Species:	O. acetosella
Binomial name
Oxalis acetosella L.

Oxalis acetosella, Otto Wilhelm Thomé Flora von Deutschland Österreich und der Schweiz (1885)

Common Wood-sorrel is a plant from the genus Oxalis, common in most of Europe and parts of Asia. It flowers for a few months during the spring, with small white flowers with pink streaks. Red or violet flowers also occur rarely. The binomial name is Oxalis acetosella, because of its sour taste. In much of its range it is the only member of its genus and hence simply known as "the wood-sorrel".

The leaflets are made up by three heart-shaped leaves, folded through the middle. The stalk is red/brown, and during the night or when it rains both flowers and leaves contract.

Historically, people have extracted calcium oxalate, or "sal acetosella" from the plant, through boiling. It is slightly toxic, as oxalic acid is known to interfere with food digestion.

The "Common wood sorrel" of North America is Oxalis montana, found from New England and Nova Scotia to Wisconsin and Manitoba and more unambiguously known as Mountain Wood-sorrel. It is similar to the species described above, but the petals are noticeably notched.

The common wood sorrel is sometimes referred to as a shamrock (due to its three-leaf clover-like motif) and given as a gift on St. Patrick's Day.

The leaves are edible and have an acid taste, leading to a common name of "sours" in the Northeast US.

References

• Blanchan, Neltje (2005). Wild Flowers Worth Knowing. Project Gutenberg Literary Archive Foundation. 

External links

Wikimedia Commons has media related to: Oxalis acetosella

• Den virtuella floran: Oxalis acetosella (Swedish)
• Giftpflanzen.com — Waldsauerklee (German)
• oxalis-acetosella.com — Oxalis acetosella (German)