Scientific name

Limnocharis Bonpl.

Common names

yellow burr head, bur head, yellow sawah lettuce, sawah-flowering rush



Native distribution

tropical America, Caribbean

Species cultivated

Limnocharis flava (L.) Buchenau

Adventive distribution

Limnocharis flava is established in India, Indonesia, Sri Lanka, Thailand, China, Singapore, with periodic outbreaks in Australia.

Weed status

Limnocharis flava is declared a prohibited weed in several countries.


emergent and rooted or floating in mats, broad-leaved rosette plant

Brief description

Perennial or annual. Plants floating or rooted and emergent. Leaves in a rosette; petiole thick, triangular in cross-section; leaf blade lanceolate, ovate to suborbicular, venation palmate with prominent mid-vein and numerous cross-veins; base squared, rounded or cordate. Inflorescence a 2-15 flowered umbel on an elongate peduncle yet shorter than the leaves. Sepals 3, green; petals, 3 yellow; stamens numerous. Dispersal by production of numerous seeds.

Natural habitat

shallow waters of lakes, ponds, and rivers

Additional comments

Limnocharis flava is the most commonly traded member of the genus. The other species from Central America, Limnocharis laforestii Duchass. ex Griseb., is not presently cultivated for ponds. It is differentiated from L. flava by the smaller flower size and the narrower leaves. Limnocharis flava is also known as puck-pai, an herb used in cooking in Thailand. Limnocharis was formerly placed in the family Limnocharitaceae.