Common names: sweetflag

Family: Acoraceae

Could be confused with: Carex, Cyperus, other sedges, Iris, Juncus, Sparganium, Vallisneria.

Native distribution: North America and Asia.

Species commonly cultivated:
Acorus calamus L. (and varieties) (Asia and North America)
A. gramineus Sol. (and varieties) (Asia)

Adventive distribution: Introduced into Europe and South America.

Weed status: Not recorded as weedy.

Habit: Reed-like, emergent.

Brief description: Perennial. Erect plant with creeping rhizome. Leaves in two sheathed rows, opposite distichous, equitant, linear, aromatic, with prominent midrib. Inflorescence a spadix, yellow-green, borne on stem that is fused with a leaf, arising approximately midway along leaf length. Spadix elongate, with numerous tiny bisexual flowers, spathe absent.

Natural habitat: Marshes, swamps, and open ponds.

Additional comments: Acorus is often regarded as a close relative of the Arum family (Araceae), and is sometimes included in that family. This plant has been found to have various medicinal, insecticidal and pharmacological qualities. Acorus spp. are used primarily as pond plants.