What invasive plant has two growth forms, one that thrives on moist soils at the edge of ponds and the other submersed?

The invasive plant that has two distinct growth forms, one flourishing in moist soils at pond edges and the other submersed, is Rotala. This plant is known for its adaptability, allowing it to thrive in various aquatic environments. The above-water growth form of Rotala typically displays vertical stems and leaves that can rise above water, while the submersed form often features more delicate structures optimized for underwater conditions. These characteristics enable Rotala to effectively invade and establish itself in different aquatic habitats, contributing to its classification as an invasive species.

In contrast, the other plants listed do not exhibit this distinct dual growth form. Hydrilla, while an invasive plant, primarily grows underwater without a significant emergent structure. Egeria, also a submersed aquatic plant, does not have a form that thrives on moist soils at the edge of ponds like Rotala does. Water Hyacinth, known for its floating leaves and colorful flowers, thrives on the water surface and does not display the same dual nature in growth forms. Understanding these differences helps in identifying invasive plants more effectively in aquatic management situations.