Alligatorweed (Alternanthera philoxeroides)
Amaranthaceae (Pigweed family)
Group: Dicot (broadleaf)
Aquatic or terrestrial mat-forming perennial plant with underground runners, native of South America. The mats are dense, tangled stems, up to 3 feet long, and float in aquatic habitats or trail in terrestrial habitats. It is found in ditches and canals and in cultivated fields.
Alligatorweed Seedling
Leaves are opposite, linear-elliptic or widest in the middle, with smooth and continuous margins. Leaves are sparsely hairy when young, without petioles or leaf stalks, and have a distinct midrib.
Stem is red or pink, can be bigger than a thumb, round, often hollow, simple or branched, 1 to 3 feet long. Stems root at nodes. Nodes have hairs and are often swollen.
Flower is a solitary head, round, and white on a long stalk.
Propagation is by vegetative means only; flowers do not produce fruits and seeds.
