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Practical information to identify and manage non-native, invasive plants and animals
The Quiet Invasion:A Guide to Invasive Species of the Galveston Bay Area | ||||||||||||||||
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Water spinach, swamp morning-glory Ipomoea aquatica
Toxic Characteristics
This species is not known to be toxic.Geographic Distribution
Currently only reported in the wild in Florida and Califonia. Continues to be sold in the Houston area, but naturalized reproducing populations have yet to be found in the area.Introduction Pathways
First introduced in 1979 in Florida, and continues to be introduced by immigrant communities who use it as an herb rich in iron.Specific Primary Habitats
Requires warm, humid conditions. A primary invader of man-made aquatic environments such as canals and ditches, and may potentially invade rice fields. Also found in natural wetlands, lakes, and river shorelines.Identifying Characteristics
As a floating herbaceous vine, it has long, branching stems containing a milky sap, with roots extending from leaf nodes. Leaves are alternate, simple, and generally arrowhead-shaped. They are 2 - 6 inches long and 0.75 - 2.25 inches wide. Petioles are 1 - 4 inches long. Flowers are white to lavender and funnel-shaped (morning-glory-like). Fruit is oval to spherical, and is 0.5 inches long and woody when mature. Fruit capsules contain 1 - 4 seeds.Reproduction Characteristics
Reproduces both vegetatively and by seed. Stem fragments and seed capsules are readily transported by water to new areas where the plant may re-colonize. In addition, nodes of existing stems readily root to establish new plants.Growth Characteristics
Water spinach can grow at a rate of 4 inches per day, producing 84 tons of fresh weight biomass per acre in 9 months. Branching stems can reach 70 feet in length.Ecological, Economic, or Social Impact
Water spinach completely covers the water surface, reducing light penetration and dissolved oxygen in water. Alters native plant and fish communities and elevates mosquito breeding. Impedes boat traffic; clogs drainage canals. Threatens rice fields.Control
Avoid introducing this plant to local waterways. Glyphosate is effective when applied to plants in dry ditches, but will affect native species as well. 2,4-D is more selective, but little is known about is effectiveness.
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Page Updated/Reviewed: 07/14/2010 8:34 AM | ||||||||||||||||