Water thyme

Description

Hydrilla verticillata, also known as Esthwaite waterweed, is often mistaken for plants from the genera Egeria and Elodea. It is a species with varying forms. Its primary distribution zones are temperate to tropical regions in Asia, Australia, Eastern Africa, and parts of Europe, although it has been introduced globally through human activity. In the USA, H. verticillata is an invasive weed that outcompetes native aquatic plants. The stems can grow up to 2 meters long and branch moderately. The plant also produces runner-like shoots and underground tuberous turions (winter buds) at their ends, allowing it to survive unfavorable periods. Each node has whorls of 3-9 leaves with serrate margins that can be seen with the naked eye. On older stem areas, internodes are typically longer than the leaves, distinguishing H. verticillata from Egeria and Elodea.