Alternathera philoxeroides

Alternanthera philoxeroides roots in wet soils or shallow water and grows out into waterways. Alternanthera philoxeroides can also grow terrestrially, forming smaller, tougher leaves. The thick mats can displace native vegetation and wildlife habitat, clog waterways, restrict oxygen levels of water, increase sedimentation, interfere with irrigation and prevent drainage. It is native to South America and was first introduced into the United States around 1900 in ballast water.

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