The dirty dozen

Cyperus difformis

Cyperus difformis

Cyperus difformis is also called small flower umbrella plant. Grows well in flooded or moist fertile soils and common in lowland rice

Cyperus iria

Cyperus iria

Cyperus iria's common names are rice flatsedge and umbrella sedge. It thrives in wetland rice, dryland annual crops, and plantation crops

Echinochloa colona

Echinochloa colona

Common names are jungle rice and awnless barnyard grass. Plant flowers throughout the year and is propagated by seeds

Echinochloa crus-galli

Echinochloa crus-galli

Also know as common barnyardgrass, this plant flowers throughout the year and can produce seeds within 60 days

Eclipta prostrata

Eclipta prostrata

Eclipta prostrata is widespread and has adapted to a range of environments. Its common name is false daisy

Fimbristylis miliacea

Fimbristylis miliacea

Its common names are lesser fimbristylis, grasslike fimbristylis, and hoorahgrass. Its seeds can germinate immediately after reaching maturity

Ischaemum rugosum Salisb.

Ischaemum rugosum Salisb.

Its common names are wrinkle duck beak and saromacca grass. Plant propagates by seeds while do not germinate while submerged

Leptochloa chinensis

Leptochloa chinensis

Leptochola chinensis is a serious weed of rice. Its ability to withstand waterlogged conditions as well as drained, moist conditions makes it a problem weed in rice

Ludwigia hyssopifolia

Ludwigia hyssopifolia

Also known as seedbox and linear leaf water primrose, this can be a serious rice weed on both clay-loam and clay soils, and in lowland rice fields

Oryza sativa

Oryza sativa

Weedy rice is highly variable and thought to originate from outcrosses to wild species (O. nivara, O. rufipogon) or as a result of outcrossing within domestic rice

Schoenoplectus juncoides

Schoenoplectus juncoides

Schoenoplectus juncoides seed germination increases under anaerobic conditions. It can also be a major weed in lowland rice fields

Sphenoclea zeylanica

Sphenoclea zeylanica

Sphenoclea zeylanica weed is reported to cause yield loss of 25−50% in rice. Young plants and tips of older plants are steamed and eaten as a vegetable in Indonesia