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An aquatic plant (Hydrilla verticillata) native to Eurasia, Africa, and Australia, having whorled, lance-shaped leaves and small white flowers. It is considered a weed in North America, where it forms large dense mats in waterways.

[New Latin, genus name, diminutive of Latin hydra, hydra; see hydra.]


(Plants) any aquatic plant of the Eurasian genus Hydrilla, growing underwater and forming large masses: used as an oxygenator in aquaria and pools. It was introduced in the S US where it has become a serious problem, choking fish and hindering navigation
[C20: New Latin, probably from hydra]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.hydrilla - submersed plant with whorled lanceolate leaves and solitary axillary flowers; Old World plant naturalized in southern United States and clogging Florida's waterways
genus Hydrilla - one species
aquatic plant, hydrophyte, hydrophytic plant, water plant - a plant that grows partly or wholly in water whether rooted in the mud, as a lotus, or floating without anchorage, as the water hyacinth
References in periodicals archive ?
Glutathione and phytochelatin played definite roles in resistance in Hydrilla verticillata (l.
Tenders are invited for Monitoring and mapping of hydrilla and other submersed aquatic vegetation (sav) in the near-shore environment of lakes beauclair, dora, carlton, griffin, eustis, harris and yale in the upper ocklawaha river basin
Hydrilla verticillata, Schinus terebinthifolius) or are recent examples of successful biological control (e.
It used to have hydrilla in it, but it's pretty much bank vegetation now.
Before beginning the salvinia project, Everitt had already started research on remote sensing of two other exotic aquatic weeds in south Texas--water-hyacinth, native to South America, and hydrilla, native to Asia.
Researchers there have discovered biological controls for many of the invasive wetland and aquatic weeds in the southern and western United States, such as melaleuca, Old World climbing fern, and hydrilla.
1,497 68 0 1,565 Egeria densa 0 9 0 9 Filamentous algae 1,381 14,636 372 16,389 Hydrilla verticillata 0 0 19 19 Hydrocotyle sp.
Habitats examined included the filamentous alga (Rhizoclonium), four native macrophytes (Ludwigia repens, Potamogeton illinoensis, Sagittaria platyphylla, and Zizania texana, which is federally listed as endangered), and the exotic macrophyte Hydrilla verticillata, as described previously (Prescott, 1970; Godfrey and Wooten, 1981; Terrell et al.
The aquatic weeds--Lemna minor (Araceae: Lemnoideae) (common name duck weed), Pistia stratiotes (Araceae: Aroideae) (common name water lettuce), Hydrilla verticillata (Hydrocharitaceae) (common name Hydrilla), and Echinodorus palaefolius var.
The state will be using an herbicide Friday in South Meadow Pond, to prevent the spread of hydrilla, according to John Woodsmall of the Clinton Conservation Commission.