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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)
Alligatorweed, flower
Credit
Photo by Chris Evans; University of Illinois
Source
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Selected Resources
The section below contains highly relevant resources for this species, organized by source.
Partnership
Federal Government
International Government
State and Local Government
Citations
Buckingham, Gary R. 1996. Biological control of alligatorweed, Alternanthera philoxeroides, the world's first aquatic weed success story. Castanea 61(3): 232–243.