Myriophyllum is a genus of aquatic plants commonly known as water milfoils. These plants are typically found in freshwater environments, such as ponds, lakes, and slow-moving rivers. They are characterized by their feathery, finely divided leaves that grow in whorls around the stem, providing a habitat for various aquatic organisms. Water milfoils can be both native and invasive species, depending on the region. Some species, like Myriophyllum spicatum, are known for their rapid growth, which can lead to dense underwater vegetation. This can impact water quality and disrupt local ecosystems, making management of invasive species important for maintaining healthy aquatic habitats.