*Alternanthera philoxeroides (Martius) Grisebach. Common name: Alligator-weed. Phenology: Mar-Oct. Habitat: Floating in mats on the surface of the waters of blackwater rivers, sloughs, ditches, ponds, and in very moist soil of ditches and shores. Distribution: Native of tropical America. This plant is a serious weed of natural areas. Reported for s. IN by Bill Thomas (pers.comm., 2022).
Origin/Endemic status: Neotropics
Synonymy ⓘ: = Ar, C, FNA4, Il, K4, NcTx, Ok, RAB, S13, Tn, Tx, Va, WH3; = Achyranthes philoxeroides (Mart.) Standl. — S; = n/a — F, Tat; Bucholzia philoxeroides Martius — (basionym)
Links to other floras: = Alternanthera philoxeroides - FNA4
Wetland Indicator Status:
- Atlantic and Gulf Coastal Plain: OBL
- Eastern Mountains and Piedmont: OBL
- Great Plains: OBL
- Midwest: OBL
Heliophily ⓘ: 9
Hover over a shape, letter, icon, or arrow on the map for definition or see the legend.




Feedback
See something wrong or missing on about Alternanthera philoxeroides? Let us know here: (Please include your name and email if at all complicated so we can clarify if needed.) We greatly appreciate feedback, and will include updates from you in our next webapp update, which can take a few months.
Horticultural Information
Intro | Stems | Leaves | Inforescence | Flowers | Fruits | Comments | Height | plant sale text | bloom table text | description | stems | leaves | inflorescence | flowers | fruits | comments | cultural notes | germination code | native range |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Ascending to reclining, mat-forming, aquatic perennial floating in mats on the surface of blackwater rivers, sloughs, ditches and ponds, and in very moist soil of ditches and shorelines. Native of tropical America. | Stems stout, mostly hollow, often red-tinged, hairy at the nodes; will root from the nodes, and in standing water will float on the surface, forming a dense, multi-layer mat with upright branches. | Leaves opposite, each pair widely spaced and at right angles to the next, sessile, the leaf base forming a sheath around stem at the node, linear to elliptic, 2--4 in. long, obscurely toothed or entire, smooth. | Flowers in compact heads on long stalks coming from upper leaf nodes, white to off-white, tiny, consisting of 5 1/4-in.-long sepals. | A serious weed of natural areas.
| 2-3 ft. | Ascending to reclining, mat-forming, aquatic perennial floating in mats on the surface of blackwater rivers, sloughs, ditches and ponds, and in very moist soil of ditches and shorelines. Native of tropical America. | Stems stout, mostly hollow, often red-tinged, hairy at the nodes; will root from the nodes, and in standing water will float on the surface, forming a dense, multi-layer mat with upright branches. | Leaves opposite, each pair widely spaced and at right angles to the next, sessile, the leaf base forming a sheath around stem at the node, linear to elliptic, 2--4 in. long, obscurely toothed or entire, smooth. | Flowers in compact heads on long stalks coming from upper leaf nodes, white to off-white, tiny, consisting of 5 1/4-in.-long sepals. | A serious weed of natural areas.
|
0 unsaved edits on this page.