Disclaimer:

The Nonindigenous Occurrences section of the NAS species profiles has a new structure. The section is now dynamically updated from the NAS database to ensure that it contains the most current and accurate information. Occurrences are summarized in Table 1, alphabetically by state, with years of earliest and most recent observations, and the tally and names of drainages where the species was observed. The table contains hyperlinks to collections tables of specimens based on the states, years, and drainages selected. References to specimens that were not obtained through sighting reports and personal communications are found through the hyperlink in the Table 1 caption or through the individual specimens linked in the collections tables.




Alternanthera philoxeroides
Alternanthera philoxeroides
(alligatorweed)
Plants
Exotic

Copyright Info
Alternanthera philoxeroides (Mart.) Griseb.

Common name: alligatorweed

Synonyms and Other Names: Pigweed, alligator weed, alligator grass, red legs, Achyranthes philoxeroides (Mart.) Standl., Alternanthera paludosa Bunbury, Alternanthera philoxerina Suess., Bucholzia philoxeroides Mart., Telanthera philoxeroides (Mart.) Moq.

Taxonomy: available through www.itis.govITIS logo

Identification: Alternanthera philoxeroides is a perennial with prostrate, sprawling, floating hollow stems, often in a dense tangled mass, rooted in shallow water or growing from the shoreline, occasionally free-floating (Long and Lakela 1971; Godfrey and Wooten 1981). The hollow stems provide considerable buoyancy of the mat (Buckingham 1996). Roots form at stem nodes. Morphology and habit of A. philoxeroides are similar to many aquatic primose (e.g., Ludwigia palustris) and hygrophila (e.g., Hygrophila costata) species.

While recognized as a major pest in aquatic environments where it has been introduced, A. philoxeroides may also grow terrestrially in moist cultivated soils (Zeiger 1967). When growing as a terrestrial, stems are smaller in diameter, more lignified, with shorter internodes. Additionally, there is variability with stems and leaves of the two recognized biotypes of A. philoxeroides. The narrow-stemmed alligatorweed (NSA) biotype have relatively slender stems and longer internodes when compared to stems of the broad-stemmed alligatorweed (BSA) biotype, which have broader stems and longer internodes (Kay and Haller 1982). There is a line of hairs on each side of the stem internodes, originating from the leaf axils and extending to the base of the next distal node (Stratford Kay, pers. comm.).

The leaves of NSA are smaller and more blunt-tipped than BSA leaves, which are larger, longer, and have an acute leaf tip (Kay and Haller 1982). In general, leaves are bright green, arranged in opposite pairs (90 degree angles), entire, elliptic-linear to ovate, 5-11 cm long and 1-2 cm wide. A leaf mid-vein is prominent on both sides of the leaf (Godfrey and Wooten 1981).

Flowers perfect (with both male and female reproductive structures), on a terminal spike (5-6 cm long), white to greenish-white, 8-10 mm in diameter, with a clover-like shape (Long and Lakela 1971; Godfrey and Wooten 1981). Vogt et al. (1992) noted wild seed production in Arkansas, Lousiana, and Mississippi populations, though none germinated.

Size: Floating stems up to 15 meters long (Zeiger 1967).

Native Range: The Parana River region of South America (Brazil, Paraguay, Argentina, and Uruguay) (Vogt et al. 1979; Julien et al. 1995).

Hydrologic Unit Codes (HUCs) Explained
Interactive maps: Point Distribution Maps

Nonindigenous Occurrences:

Table 1. States with nonindigenous occurrences, the earliest and latest observations in each state, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Alternanthera philoxeroides are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
AL1897202319Cahaba; Guntersville Lake; Locust; Lower Coosa; Lower Tallapoosa; Middle Alabama; Middle Chattahoochee-Walter F; Middle Tennessee-Elk; Middle Tombigbee-Chickasaw; Middle Tombigbee-Lubbub; Mississippi Coastal; Mobile Bay; Mobile-Tensaw; Noxubee; Pea; Perdido Bay; Upper Alabama; Upper Choctawhatchee; Wheeler Lake
AR1968202321Bayou Bartholomew; Bayou Macon; Bayou Meto; Boeuf; Dardanelle Reservoir; Fourche La Fave; Lake Conway-Point Remove; Little Missouri; Loggy Bayou; Lower Arkansas; Lower Arkansas-Maumelle; Lower Mississippi Region; Lower Mississippi-Helena; Lower Mississippi-St. Francis; Lower Ouachita-Smackover; Lower Saline; Lower St. Francis; Lower White; McKinney-Posten Bayous; Ouachita Headwaters; Upper Saline
CA1946202213Honcut Headwaters-Lower Feather; Los Angeles; San Diego; San Gabriel; San Luis Rey-Escondido; Santa Ana; Santa Barbara Coastal; Suisun Bay; Tulare Lake Bed; Tulare-Buena Vista Lakes; Upper Kaweah; Upper Tule; Ventura
FL1894202452Alafia; Alapaha; Apalachee Bay-St. Marks; Apalachicola; Apalachicola Bay; Aucilla; Big Cypress Swamp; Blackwater; Caloosahatchee; Cape Canaveral; Charlotte Harbor; Chipola; Crystal-Pithlachascotee; Daytona-St. Augustine; Econfina-Steinhatchee; Escambia; Everglades; Florida Bay-Florida Keys; Florida Southeast Coast; Floridian; Hillsborough; Kissimmee; Lake Okeechobee; Little Manatee; Lower Chattahoochee; Lower Choctawhatchee; Lower Ochlockonee; Lower St. Johns; Lower Suwannee; Manatee; Myakka; Nassau; New; Oklawaha; Peace; Pensacola Bay; Perdido; Santa Fe; Sarasota Bay; South Atlantic-Gulf Region; St. Andrew-St. Joseph Bays; St. Marys; Suwannee; Tampa Bay; Upper St. Johns; Upper Suwannee; Vero Beach; Waccasassa; Western Okeechobee Inflow; Withlacoochee; Withlacoochee; Yellow
GA1965202224Alapaha; Altamaha; Canoochee; Cumberland-St. Simons; Little; Little Satilla; Lower Flint; Lower Ocmulgee; Lower Oconee; Lower Ogeechee; Lower Savannah; Middle Chattahoochee-Lake Harding; Middle Chattahoochee-Walter F; Middle Savannah; Ogeechee Coastal; Satilla; Spring; St. Marys; Upper Chattahoochee; Upper Flint; Upper Ocmulgee; Upper Oconee; Upper Ogeechee; Withlacoochee
KY198619882Kentucky Lake; Upper Cumberland
LA1927202244Amite; Atchafalaya; Atchafalaya - Vermilion; Bayou Cocodrie; Bayou Sara-Thompson; Bayou Teche; Boeuf; Boeuf-Tensas; Calcasieu-Mermentau; Castor; East Central Louisiana Coastal; Eastern Louisiana Coastal; Lake Maurepas; Lake Maurepas; Lake Pontchartrain; Liberty Bayou-Tchefuncta; Little; Louisiana Coastal; Lower Calcasieu; Lower Grand; Lower Mississippi; Lower Mississippi Region; Lower Mississippi-Lake Maurepas; Lower Mississippi-New Orleans; Lower Ouachita; Lower Ouachita; Lower Pearl; Lower Red; Lower Red; Lower Red-Lake Iatt; Lower Red-Ouachita; Lower Sabine; Mermentau; Mermentau Headwaters; Red-Saline; Red-Sulphur; Sabine Lake; Tangipahoa; Tensas; Tickfaw; Upper Calcasieu; Vermilion; West Central Louisiana Coastal; Whisky Chitto
MD201420212Middle Potomac-Anacostia-Occoquan; Middle Potomac-Catoctin
MS1949202330Bear; Big Sunflower; Black; Bogue Chitto; Buffalo; Deer-Steele; Escatawpa; Homochitto; Little Tallahatchie; Lower Chickasawhay; Lower Leaf; Lower Pearl; Middle Pearl-Silver; Middle Pearl-Strong; Middle Tombigbee-Lubbub; Mississippi Coastal; Noxubee; Pascagoula; Pascagoula; Pickwick Lake; Sucarnoochee; Tallahatchie; Tangipahoa; Tibbee; Town; Upper Big Black; Upper Leaf; Upper Pearl; Upper Tombigbee; Upper Yazoo
NC1957202429Albemarle; Albemarle-Chowan; Blackwater; Cape Fear; Chowan; Coastal Carolina; Contentnea; Haw; Lower Cape Fear; Lower Catawba; Lower Neuse; Lower Pee Dee; Lower Roanoke; Lower Tar; Lumber; Meherrin; Middle Roanoke; New River; Northeast Cape Fear; Pamlico; Pamlico Sound; Rocky; Santee; South Fork Catawba; Upper Cape Fear; Upper Catawba; Upper Neuse; Upper Pee Dee; Waccamaw
OK199620205Dirty-Greenleaf; Lower Cimarron-Skeleton; Lower Verdigris; Robert S. Kerr Reservoir; Upper Little
PR196320225Cibuco-Guajataca; Culebrinas-Guanajibo; Eastern Puerto Rico; Puerto Rico; Southern Puerto Rico
SC1945202225Black; Broad-St. Helena; Bulls Bay; Carolina Coastal-Sampit; Congaree; Cooper; Edisto River; Edisto-Santee; Edisto-South Carolina Coastal; Lake Marion; Little Pee Dee; Lower Broad; Lower Catawba; Lower Pee Dee; Lower Pee Dee; Lower Savannah; Lumber; Middle Savannah; North Fork Edisto; Salkehatchie; Saluda; Santee; Santee; South Carolina Coastal; Waccamaw
TN197520179Holston; Kentucky Lake; Lower Cumberland; Lower Tennessee; Lower Tennessee-Beech; Middle Tennessee-Chickamauga; Stones; Tennessee Region; Watts Bar Lake
TX1975202452Austin-Oyster; Austin-Travis Lakes; Buffalo-San Jacinto; Caddo Lake; Cedar; Chambers; East Fork Trinity; East Galveston Bay; East Matagorda Bay; East Matagorda Bay; Elm Fork Trinity; Lake Fork; Lake O'the Pines; Little Cypress; Little Wichita; Lower Angelina; Lower Brazos; Lower Colorado-Cummins; Lower Guadalupe; Lower Neches; Lower Nueces; Lower Sabine; Lower San Antonio; Lower Sulpher; Lower Trinity; Lower Trinity-Kickapoo; Lower West Fork Trinity; Middle Brazos-Palo Pinto; Middle Guadalupe; Middle Sabine; Navasota; Navidad; North Bosque; North Galveston Bay; Sabine Lake; San Bernard; San Gabriel; San Marcos; South Corpus Christi Bay; South Laguna Madre; Spring; Toledo Bend Reservoir; Upper Angelina; Upper Neches; Upper Sabine; Upper San Antonio; Upper Trinity; Upper West Fork Trinity; West Fork San Jacinto; West Galveston Bay; White Oak Bayou; Yegua
VA195620217Albemarle; Blackwater; Chowan; Hampton Roads; Lower James; Lynnhaven-Poquoson; Middle Potomac-Anacostia-Occoquan

Table last updated 12/1/2024

† Populations may not be currently present.


Ecology: Like dense, floating mats of Eichhornia crassipes, A. philoxeroides can form dense floating mats and, with the subsequent build-up of organic detritus in the mat, can create an environment that supports the growth of emergent aquatic and terrestrial species, including woody species such as Salix spp. and Cephalanthus occidentalis. These floating islands (also referred to as tussocks, sudds, and flotants), accelerate succession and create concern for quality aquatic habitat, navigation and infrastructure (Russell 1942; Penfound and Earle 1948).

Plants produce viable seed in its native range, but observed seeds were all non-viable in its adventive range (Vogt et al. 1992). Reproduction is thought to be entirely through vegetative means. Stem fragments produce roots at stem nodes that can float to new locations, rooting in the subsurface soils producing new colonies. Along with stem nodes, vegetative reproduction can also occur from thick root mass and underground stem fragments (Sainty et al. 1998).

Alligatorweed may grow in waters deeper than 2.5 meters (Stratford Kay, pers. comm.), but must remain rooted in hydrosoil for optimum growth (Sculthorpe 1967). Plants can uproot, drift, and establish in new locations, but they cannot compete if unrooted for long periods of time (Sculthorpe 1967). The mat can extend up to 15 meters from where it is rooted in the soil (Zeiger 1967), but mats were observed much further from banks in Mississippi and North Carolina populations where they rooted into stumps and small trees (Stratford Kay, pers. comm.).

The introduced alligatorweed flea beetle (Agasicles hygrophila Selman and Vogt), along with other introduced insects, have provided exceptional biological control for this species. However, the northern spread of A. philoxeroides is beyond the range of the introduced insect's ability to overwinter. The flea beetle produces the most damage to A. philoxeroides plants and can only survive winters where the mean January temperature is 11°C or warmer, which includes Florida and coastal areas of the southeastern U.S. (Buckingham 1996). However, the introduced alligatorweed stem borer (Vogtia malloi) has produced more damage to A. philoxeroides in the interior regions of alligatorweed’s adventive range than has the flea beetle in the southern and coastal regions (Vogt et al. 1992).

Means of Introduction: Alternanthera philoxeroides was first recorded in the US in 1897 near Mobile, Alabama. The plant was present in New Orleans in 1898 (Zeiger 1967; Coulson 1977). Plants are believed to have been contaminants in ship ballast water (Zeiger 1967).

Status: Established in all previously mentioned areas.

Impact of Introduction:
Summary of species impacts derived from literature review. Click on an icon to find out more...

EcologicalEconomicHuman HealthOther




After its introduction into the US in the late 1800’s, A. philoxeroides quickly spread throughout the Southeast creating problems similar to those described for Eichhornia crassipes (Penfound and Earle 1948; Zeiger 1967). Following the development of the herbicide 2,4-D in the 1940’s, aggressive herbicide spraying initiated against E. crassipes allowed for A. philoxeroides, which was more resistant to the herbicide, to replace the niche formerly occupied by E. crassipes. By 1963, as estimated 65,700 hectares of waters throughout the Southeast were infested (Buckingham 1996). As a result, in 1959, the US Army Corps of Engineers (USACE), under the “Expanded Project for Aquatic Plant Control” authorized by Public Law 85-500, 85th Congress, requested the Agricultural Research Service, USDA, to begin surveys for A. philoxeroides natural enemies in South America (Zeiger 1967). In 1964, the USDA began releasing imported insects from South America as a biocontrol for this pest. Extensive testing and quarantine procedures were completed prior to release (Zeiger 1967). By all accounts, the insects that were approved and subsequently released against A. philoxeroides have been successful in managing this pest plant, although the effectiveness of alligatorweed thrips (Amynothrips andersoni), which are flightless and rarely seen on wild populations, is questionable (Stratford Kay, pers. comm.).

Remarks: The Aquatic Plant Control Program staff with the USACE Jacksonville District, upon request, annually coordinates the shipment of flea beetles (Agasicles hygrophila) collected in the St. Johns River in Florida to areas of the country where the flea beetles do not overwinter and alligatorweed persists.

References: (click for full references)

Anderson, L.C. (curator). 2009. Herbarium Specimen Voucher Data, Florida State University (FSU), Herbarium. Florida State University, Tallahassee, FL. http://herbarium.bio.fsu.edu/.

Aurand, D. 1982. Nuisance Aquatic Plants and Aquatic Plant Management Programs in the United States. Volume 2, Southeast. The MITRE Corporation, McLean, VA.

Buckingham, G.R. 1996. Biological control of alligatorweed, Alternanthera philoxeroides, the world's first aquatic weed success story. Castanea 61(3):232-243.

Calflora. 2015. The Calflora Database. http://www.calflora.org/. Accessed on 12/04/2015.

Carter, R. (curator). 1999. Herbarium specimen voucher data, Valdosta State University Herbarium (VSC). Valdosta State University, Valdosta, GA. http://herb.valdosta.edu/.

Center for Invasive Species and Ecosystem Health. 2015. EDDMapS: Early detection and distribution mapping system. The University of Georgia, Tifton, GA. http://www.eddmaps.org.

Chester, E.W. 1988. Alligatorweed, Alternanthera philoxeroides (Mart.) Griseb. in Kentucky. Transactions of the Kentucky Academy of Science 49(3/4):140-142.

Chester, E.W., B.E. Wofford, and R. Kral. 1997. Atlas of Tennessee Vascular Plants Volume 2. Angiosperms: Dicots. Volume 2. Center for Field Biology, Austin University, Clarksville, TN.

Coulson, J.R. 1977. Biological control of alligatorweed, 1959-1972. US Department of Agriculture, Washington, DC.

Craft, B.R., and D. Kleinpeter. 1989. Vegetation and salininty changes following the installation of a fixed crest weir at Avery Island, LA. US Fishand Wildlife Service and Louisiana Dept of Natural Resources.

Godfrey, R.K., and J.W. Wooten. 1981. Aquatic and Wetland Plants of the Southeastern United States, dicotyledons. University of Georgia, Athens, GA.

Helton, R.J., and L.H. Hartmann. 1996. Statewide Aquatic Vegetation Survey Summary, 1995 Report. Inland Fisheries Division, District 3-E, Jasper, Texas.

Hoagland, B.W., and N.A. McCarty. 1998. Noteworthy Collections: Oklahoma. Castanea 63(2):194.

Hooker, K.L., and H.M. Westbury. 1991. Development of wetland plant communities in a new reservoir. Pages 45-60 in Webb, F.J, ed. Proceedings of the 18th Annual Conference on Wetlands Restoration and Creation. Hillsborough Community College. Tampa, FL.

Julien, M.H., B. Skarratt, and G.F. Maywald. 1995. Potential geographical distribution of alligator weed and its biological control by Agasicles hygrophila. Journal of Aquatic Plant Management 33:55-60. http://www.apms.org/japm/vol33/v33p55.pdf.

Kay, S.H., and W.T. Haller. 1982. Evidence for the existence of distinct alligtorweed biotypes. Journal of Aquatic Plant Management 20:37-41.

Kight, J. 1988. Tennessee-Tombigbee Waterway. Pages 324-329 in Proceedings of the 22th Annual Meeting on Aquatic Plant Control Research Programs. U.S. Army Corps of Engineers, Waterways Experiment Station. Vicksburg, MS.

Long, R.W., and O. Lakela. 1971. A flora of tropical Florida. University of Miami Press, Coral Gables, FL.

Louisiana State University Herbarium. 2010. Louisiana State University Herbarium - Vascular Plants. Louisiana State University, Baton Rouge, LA. http://www.gbif.org/dataset/56e9c560-bd2a-11dd-b15e-b8a03c50a862. Created on 05/03/2010. Accessed on 11/20/2015.

Lynch, J.J., J.E. King, T.K. Chamberlain, and A.L. Smith, Jr. 1950. Effects of aquatic weed infestations on the fish and wildlife of the Gulf states. US Dept of the Interior, Fish and Wildlife Service Special Scientific Report No 39.

Madsen, J.D. 2010. Invasive Plant Atlas of the MidSouth. Geosystems Research Institute, Mississippi State University, Starkville, MS. http://www.gri.msstate.edu/ipams/.

Madsen, J.D., G. Ervin, V. Maddox, & C. Abbott. 2010. Invasive Plant Atlas of the MidSouth. Mississippi State University. http://www.gri.msstate.edu/research/ipams/contactinfo.php.

Mississippi River Basin ANS Regional Panel. 2006. Mississippi River Basin ANS Regional Panel Annual Report to the ANS Task Force (9/1/05 to 8/31/06).

Missouri Botanical Garden. 2007. Missouri Botanical Garden. Missouri Botanical Garden, St. Louis, MO. http://www.gbif.org/dataset/7bd65a7a-f762-11e1-a439-00145eb45e9a. Created on 04/02/2007. Accessed on 11/20/2015.

Montz, G.N. 1979. Distribution of selected aquatic species in Louisiana. US Army Corps of Engineers, New Orleans, LA.

New York Botanical Garden. 2015. The New York Botanical Garden Herbarium (NY) - Vascular Plant Collection. The New York Botanical Garden, New York, NY. http://www.gbif.org/dataset/d415c253-4d61-4459-9d25-4015b9084fb0. Created on 06/18/2015. Accessed on 11/20/2015.

Newman, M.J., and W.W. Thomaston. 1979. Aquatic weed control in Georgia. Proceedings of the Southern Weed Science Society 32:271-279.

North Carolina Division of Water Resources. 1996. Economical and Environmental Impacts of N.C. Aquatic Weed Infestations. North Carolina Department of Environment, Health, and Natural Resources, Raleigh, NC.

Penfound, W.T., and T.T. Earle. 1948. The biology of water hyacinth. Ecological Monographs 18(4):447-472.

Radford, A.E., H.E. Ahles, and C.R. Bell. 1968. Manual of the Vascular Flora of the Carolinas. Univ North Carolina Press, Chapel Hill.

Regents of the University of California. 2015. Jepsen online interchange for California floristics. University and Jepson Herbaria, University of California, Berkeley. http://ucjeps.berkeley.edu/interchange.html.

Reimus, R.G., and W.B. Robertson, Jr. 1997. Plants of Dry Tortugas National Park: an annotated list and expanded checklist. Miami, FL: Institute for Regional Conservation:28 pp.

Russell, R.J. 1942. Flotant. Geographical Review 32(1):74-98.

Sainty, G., G. McCorkelle, and M. Julien. 1998. Control and spread of alligator weed Alternanthera philoxeroides (Mart.) Griseb., in Australia: lessons for other regions. Wetlands Ecology and Management 5:195-201.

Schardt, J.D., and D.C. Schmitz. 1991. 1990 Florida aquatic plant survey. Technical report #91-CGA Florida Department of Natural Resources, Bureau of Aquatic Plants, Tallahasee, FL.

Sculthorpe, C.D. 1967. The biology of aquatic vascular plants. Edward Arnold, London, UK.

Smith, E.B. 1988. An atlas and annotated list of the vascular plants of Arkansas. 2nd edition. University of Arkansas, Fayetteville, AR. www.csdl.tamu.edu/FLORA/arkansas.

Southeast Exotic Pest Plant Council. 2008. Early Detection & Distribution Mapping System. University of Georgia Center for Invasive Species and Ecosystem Health. http://www.se-eppc.org/eddmaps/index.cfm.

Texas Invasive Plant and Pest Council. 2015. Texas Invasives Database. http://www.texasinvasives.org/. Accessed on 11/20/2015.

Thomas, R.D., and C.M. Allen. 1996. Atlas of the Vascular Flora of Louisiana Volume II: Dicotyledons Acanthaceae - Euphorbiaceae. Volume 2. Bourque Printing, Inc Baton Rouge, LA.

University of Alabama Biodiversity and Systematics. 2007. Herbarium (UNA). University of Alabama, Tuscaloosa, AL. http://www.gbif.org/dataset/84f9770e-f762-11e1-a439-00145eb45e9a. Created on 04/03/2007. Accessed on 11/20/2015.

University of Connecticut. 2011. CONN. University of Connecticut, Storrs, CT. http://www.gbif.org/dataset/5288946d-5fcf-4b53-8fd3-74f4cc6b53fc. Created on 09/08/2011. Accessed on 11/20/2015.

University of Florida Herbarium. 2016. Florida Museum of Natural History. University of Florida, Gainesville, FL. http://www.flmnh.ufl.edu/herbarium/.

Valentine, J.M. 1976. Plant succession after saw-grass mortality in southwestern Louisiana. Proceedings of the 13th Annual Conference. SE Assoc. Fish and Wildlife Agencies, 24-27 October 1976, Jackson, MS:634-640.

Vogt, G.B., J.U. McGuire, Jr., and A.D. Cushman. 1979. Probable evolution and morphological variation in South American Disonychine flea beetles (Coleoptera : Chrysomelidae) and their Amaranthaceous hosts. United States Department of Agriculture Science and Education Administration, Washington, D.C.

Vogt, G.B., P.C. Quimby, Jr., and S.H. Kay. 1992. Effects of weather on the biological control of alligatorweed in the Lower Mississippi Valley Region, 1973-83. U.S. Department of Agriculture Technical Bulletin 1766.

Ware, D. (director). 1998. Herbarium specimen voucher data, Herbarium of the College of William & Mary (WILLI). College of William and Mary, Williamsburg, VA. http://www.wm.edu/as/biology/about/facilities/herbarium/.

White, D.A. 1993. Vascular plant community development on mudflats in the Mississippi River Delta, Louisiana, USA. Aquatic Botany 45:171-194.

Wofford, B.E. 1977. State Records and Other Recent Noteworthy Collections of Tennessee Plants II. Castanea 42(3):190-193.

Woffard, B.E., and W.M. Dennis. 1976. State Records and other Recent Noteworthy Collections. Castanea 41(2):119-120.

Zeiger, C.F. 1967. Biological control of alligatorweed with Agasicles n. sp. in Florida. Journal of Aquatic Plant Management 6:31-34. http://www.apms.org/japm/vol06/v6p31.pdf.

Zeiger, C.F. 1976. Aquatic plant problems in Puerto Rico. Pages 24-25 in Proceedings, Research Planning Conference on the Aquatic Plant Control Program, 22-24 October 1975. U.S. Army Engineer Waterways Experiment Station. Vicksburg, MS.

Author: Thayer, D.D., and I.A. Pfingsten

Revision Date: 8/30/2023

Peer Review Date: 4/4/2016

Citation Information:
Thayer, D.D., and I.A. Pfingsten, 2024, Alternanthera philoxeroides (Mart.) Griseb.: U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=227, Revision Date: 8/30/2023, Peer Review Date: 4/4/2016, Access Date: 12/1/2024

This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.

Disclaimer:

The data represented on this site vary in accuracy, scale, completeness, extent of coverage and origin. It is the user's responsibility to use these data consistent with their intended purpose and within stated limitations. We highly recommend reviewing metadata files prior to interpreting these data.

Citation information: U.S. Geological Survey. [2024]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [12/1/2024].

Contact us if you are using data from this site for a publication to make sure the data are being used appropriately and for potential co-authorship if warranted.

For general information and questions about the database, contact Wesley Daniel. For problems and technical issues, contact Matthew Neilson.