Duckweed Center

The Sonar® Solution

If you're frustrated by a duckweed problem on your pond, Sonar Aquatic Herbicide from SePRO Corporation is the answer. Dedicated to advancing the science of aquatic plant management, SePRO has conducted over 6 years of extensive research on product formulations, release rates and pond sediment to discover how these three critical factors affect plant control. As the culmination of this research, professional aquatic managers now choose from 8 distinct formulations of Sonar, the world's leading brand of aquatic herbicide for the selective, long-term control of undesirable aquatic vegetation. For small pond owners seeking to control duckweed, the aqueous solution of Sonar, or Sonar A.S., is the ideal formulation.

Just one Sonar A.S. treatment is able to control duckweed for a year or longer, no other aquatic herbicide is more effective on this troublesome aquatic vegetation. Sonar A.S. is easy-to-apply, is available for immediate uptake into the target plants and is the ideal choice in water bodies with minimal water flow and when targeting strands of floating vegetation such as duckweed. Sonar selectively manages problem weeds for a year or longer with minimal risk to the environment. That makes water usable for recreation, brings the fish and native plant populations back into balance and restores property values. Water can be enjoyed the way it used to be, because even directly after application, Sonar won't restrict swimming, fishing or drinking. No other aquatic herbicide provides this flexibility.

Aquatic herbicides can be classified as systemic or contact and selective or non-selective. The systemic action of Sonar provides unmatched control because the active ingredient, fluridone, is absorbed from the water into each target plant’s roots, stems and leaves. For best control, treatment takes place during periods of active growth so the herbicide can move throughout the plant. One Sonar treatment eliminates even the most stubborn duckweed for a year or longer while allowing pond owners to restore native plant and wildlife habitats. Contact herbicides affect only the portion of the plant tissue on which they land. Contact herbicides may control some small annual weeds but only provide temporary burn-back on perennial weeds such as duckweed.

In addition, the quick action of contact herbicides can lead to oxygen depletion and fish kills due to the accelerated decomposition of the dead plant material. Sonar causes a slow degradation of photosynthetic activity in nuisance aquatic vegetation such as duckweed. In addition to duckweed control that often lasts for several growing seasons, the slow action of Sonar greatly reduces the chance of negatively affecting the fish in your pond that could be caused by rapidly decaying vegetation. Finally, selective herbicides like Sonar will only control specific plants. For example, Sonar eliminates the targeted duckweed while leaving beneficial, native vegetation unharmed. On the other hand, a non-selective herbicide has the potential to kill or injure any plant with which it comes into contact.

No other product offers the combination of long-term, effective control of duckweed for the money that Sonar provides. Instead of torching your duckweed with a non-selective contact herbicide only to see it return within a month while your fish and beneficial native plants struggle to survive, rely on the systemic, selective action of Sonar and restore your pond to its natural state without having to reapply for up to 2 years.

Aquatic Specialists from SePRO have used Sonar to restore thousands of weed-infested acres on large water bodies throughout the world. SePRO pond advisors rely on the entire company's knowledge database to provide experienced, professional assistance to pond enthusiasts like you. A SePRO pond advisor is just a phone call or e-mail away and will be happy to assist you with the diagnosis and management of your duckweed problem or any other question regarding the maintenance of your pond.