Floating pondweed

Floating pondweed (Potamogeton natans) belongs to the Potamogetonaceae family. It is a perennial aquatic plant classified as a rhizomatous hydrophyte. Its life strategy is centered around rapid vegetative reproduction and the colonization of open water bodies.

The primary habitat for this plant includes freshwater bodies with standing or slow-moving water. In agronomy, Floating pondweed is considered a troublesome weed in irrigation systems. It thrives in canals, reservoirs, and rice paddies, where it reduces the hydraulic capacity of water structures and hinders the distribution of irrigation water.

The biology of Potamogeton natans is characterized by a robust root system that overwinters in the benthic mud. The plant exhibits a high capacity for regeneration from even small rootstock fragments. It possesses dimorphic leaves: submerged linear leaves and floating leathery elliptical leaves, which provide the plant with high resistance to temperature fluctuations and mechanical stress.

The harmfulness of this weed lies in its ability to significantly decrease water flow velocity in canals, leading to increased siltation. In rice cultivation, it competes with crops for space, nutrients, and sunlight. Dense mats prevent proper water heating, which directly impacts the overall crop yield.

Control measures require an integrated approach. Agrotechnical methods include regular canal maintenance and winter drainage to ensure the freezing of rootstocks. Chemical control involves the use of glyphosate or diquat-based herbicides, subject to specific regional water-use regulations. Recommended management practices:

• Mechanical removal using aquatic weed cutters and harvesters.
• Preventive water level management in canals.
• Localized application of authorized aquatic herbicides.