It may seem convenient and cost-effective to use your terrestrial weed herbicides to treat weeds in your pond or lake, but when it comes to managing nuisance growth in and around your pond, not all chemicals are created equally.
Though broad-spectrum-use herbicides work great on grassy terrestrial weeds, they're not approved for use on cattails and water milfoil because of the direct contact with public waterways or the possibility of leaching into drinking/groundwater. Instead, you need to use products that are registered by the Environmental Protection Agency for aquatic use, like Algae Defense, Aquathol and Shoreline Defense Emergent Weed Control aquatic herbicides.
Why the regulations? Read on for details.
Environmental Protection
The EPA registers products like herbicides for aquatic use to protect the environment. Its goal is to minimize harm while maximizing results.
The government agency tests the ingredients' concentration, frequency of use and effectiveness for their short-term and long-term effects in their intended environment. It also checks the chemicals' half-life, which is how long the substances remain in the environment before breaking down enough to be considered non-toxic.
Safer for Your Pond Visitors
If you use unapproved chemicals in your pond or lake, you could be doing harm to not only the ecosystem but also to your fish, your livestock, and wildlife, your soil and, most importantly, to yourself, your family and your neighbors.
Herbicides that have been approved by the EPA include specific restrictions and precautions on their labels about consuming fish after treating bodies of water. They caution against swimming in or drinking from treated ponds within a certain amount of time after application. They even warn of soil contamination issues that landowners or pond professionals should be aware of.
Chemicals that are not approved for aquatic use have none of these warnings because they have not been tested for their effects on the pond habitat. In fact, some products can actually be considered a contaminant to the aquatic environment - and you don't want that, right?
Obey the EPA
Even if you don't consume your game fish, swim in your lake or drink the water, you should steer clear of unapproved chemicals. Some of them can leach into the soil surrounding the pond or be released during heavy rains when ponds flood. That runoff - including the potentially toxic chemicals - can then be released into the public waterways or wetlands used by neighbors.
Play it safe. Obey the EPA.