Latin name

Marsilea minuta L.

Family

Marsileaceae

Common name(s)

Water fern

Synonym(s)

Marsilea mollis B. L. Rob. & Fernald (accepted)

Geographical distribution

South and Southeast Asia: Bangladesh, Cambodia, India, Indonesia, Lao PDR, Malaysia, Pakistan, Philippines, Sri Lanka, Thailand, and Vietnam.

Rest of the world: America (North and Central) and Africa, including Madagascar.

Morphology

A perennial fern with hairy, creeping rhizomes.

Stem: long, slender, and branched creeping rhizomes; leaf petiole 10—30—cm—long when growing in water or 2—cm—long when on dry mud.

Leaf: fronds with 4 but rarely 2 or 3 leaflets: leaflet triangular with a round apex and non-entire or wedge-shaped base, 10—15—mm—long.

Sporocarps: small, about 3—mm—long; in pairs; attached at the very base of petiole of fern leaf.

Biology and ecology

Common in wetland rice, muddy places, shallow pools, and flooded areas; has creeping rhizomes that are buried shallowly in mud; floats on water surface; reproduced primarily by its rhizomes, and also by spores.

Agricultural importance

A weed of wetland rice that can compete strongly with rice seedlings.

Management

Cultural control: thorough hand weeding or hand pulling can easily remove shallow rhizomes.

Chemical control: can be controlled by postemergence application of bensulfuron-methyl, cinosulfuron, and 2,4-D in rice; also by oxyfluorfen as preemergence treatment.

Selected references

Achlderon KI, Hare CJ, Palis FV, Burhan H, Bhandhufalck A, Chong WC. 1987. Setoff: a new rice herbicide for S.E. Asia. In: Proceedings of the 11th Asian Pacific Weed Science Society Conference. Taipeh, Taiwan: Asian Pacific Weed Science Society. p 73-79.

Burhan H, Sozzi D, Zoschke A. 1989. Setoff for weed control in rice: practical experience from Indonesia. Proceedings, 12th Asian-Pacific Weed Science Society Conference. No. 1:127-131.

Moody K. 1989. Weeds reported in South and Southeast Asia. Manila (Philippines): International Rice Research Institute. 442 p.

Moody K, Munroe CR, Lubigan RT, Paller Jr. EC. 1984. Major weeds of the Philippines. Weed Science Society of the Philippines. College, Laguna (Philippines): University of the Philippines at Los Baños. 328 p.

Parker C. 1992. Weeds of Bhutan. National Plant Protection Centre Simtokha, Royal Government of Bhutan. 236 p.

Pancho JV, Soerjani M. 1978. Aquatic weeds of Southeast Asia: a systematic account of common Southeast Asian aquatic weeds. Bogor (Indonesia): SEAMEO Regional Center for Tropical Biology. 130 p.

Peudpaichit S, Tongchairawewat P, Simagrai M, 1987. Londax + BAS 514.H: a broad spectrum weed control treatment in rice. In: Proceedings, 11th Asian Pacific Weed Science Society Conference, Taipei. Taiwan: Asian Pacific Weed Science Society. No. 2:437-448.

Rodgers JA, 1993. Aquatic four leaf clovers: Marsilea spp. Aquatics 15:10-13.

Yasin HG, Pandang MS, Bahar FA. 1988. Performance of oxyfluorfen as preemergence herbicide in transplanted and direct seeded rice. Weedwatcher 6/7:6.

Contributors

JLA Catindig, RT Lubigan, and DE Johnson