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Alligatorweed

Scientific Name

Alternanthera philoxeroides (Mart.) Griseb. (ITIS)

Common Name

Alligatorweed, alligator weed, pig weed

Synonym

Achyranthes philoxeroides (ITIS)

Native To

South America (Spencer and Coulson 1976)

Date of U.S. Introduction

First reported in Alabama in 1897 (Buckingham 1996)

Means of Introduction

Possibly introduced through ballast water (Buckingham 1996)

Impact

Forms dense mats that crowd out native species and impede recreational activities such as boating, swimming, and fishing (Texas Invasives 2007)

Current U.S. Distribution

Southeastern U.S., California

Alligatorweed

Alligatorweed, flower

Credit

Photo by Chris Evans; University of Illinois

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Distribution / Maps / Survey Status

Videos

Selected Resources

The section below contains highly relevant resources for this species, organized by source.

Partnership
Federal Government
International Government
State and Local Government
Academic
Citations