What is the main reproduction technique used by watermilfoil?

Watermilfoil primarily reproduces through fragmentation, which is a process where parts of the plant break off and establish themselves as new individuals. This method allows watermilfoil to spread rapidly and occupy large areas of water bodies. When fragments of the plant are disturbed, whether by natural events like water movement or human activities such as boating or fishing, they can form a new plant wherever they land, which contributes to the invasive nature of the species.

While seed propagation, rhizomes, and tubers are other forms of reproductive or survival strategies in aquatic plants, they are not the dominant method for watermilfoil. Seed propagation occurs but is less common in watermilfoil, as conditions need to be just right for seeds to germinate and grow. Rhizomes and tubers are more common in some aquatic plants for nutrient storage and propagation, but watermilfoil's ability to reproduce extensively through fragmentation is what makes it particularly invasive in many aquatic ecosystems.