Invasive Alien Species
Species Name: Hydrilla verticillata
- Family Name:
- Not clear perhaps southern, southeastern Asia and Australia.
- Submerged freshwater plants, 25-300 cm long, profusely rooting in the mud, often with subter4ranean stolons with swollen top, densely covered with scales, 4-5 x 2.5 – 6 mm. Stem are distinctly divided into nodes and internodes, and may be up to 5 5 m long in deep water. Leaves in whorls of 3-8, linear to ovate, sharply dentate, 8-40 mm x 1-5 mm.
Flowers develop singly within spathes in leaf axils, usually one female flower or several male flowers together in the upper nodes, with long peduncle, white or reddish; the male spathes contain a single flower 3 mm across, which released from the spathe just before maturity and floats up to the surface. Fruit elongate, 2-6 seeded; seed dark brown. Axillary turions green are formed in theaxil of a leaf and stalk, 3-12 x 2-3.5 mm.
- Invaded Habitat:
- In ditches, pools, ponds, marshes, shallow, muddy rivers; often abundant; also in tidal waters. It can go down 6-12 m, in which case, it will not reach the surface. In turbulent waters the plant remains bottom-bound. Lowland-irrigated, lebak and tidal rice fields.
- Widespread throughout Indonesia.
- The plant spreads mainly by vegetative reproduction, e.g. by stolons, tubers, turions and stem fragments. Grow is strongly enhanced with increasing nutrient content of the water. The plant accumulates a bank of tubers and turions in the soil that may persist for several years. The plant usually dies back above-ground at the end of the growing season. Growing from 0-2000 m alt.
- Backer , C. A. & R. C. Bakhuizen Van Den Brink. 1965. Flora of Java. N.V. P. Noordhoff. Groningen, Netherlands.
- Budiman, A., M. Thamrin and S. Asikin. 1988. Beberapa Jenis Gulma di Lahan Pasang Surut Kalimantan Selatan dan Tengah dengan Tingkat Kemasaman Tanah Yang Berbeda. Dalam Prosiding Konferensi HIGI IX.
- Soerjani, M., A. J. G. H. Kostermans & Gembong Tjitrosoepomo (Eds.). 1987. Weeds of Rice in Indonesia. Balai Pustaka. Jakarta.
- Swarbrick, J.T., C.M. Finlayson and A.J. Cauldwell. 1982. The Biology and Control of Hydrilla verticillata (L.F.) Royle. BIOTROP Special Publication No. 16.
- Weber, E. 2003. Invasive Plant Species of the World. A Reference Guide to Environmental Weeds. CAB International Publishing