Frequently Asked Questions

Q. How long before I see results?

Algae impact can be seen same day and usually will succumb within five to seven days. Weeds on average will drop from the water column and decompose on average from eight to fifteen days after treatment - some sooner - some a bit longer. Nuisance type, time of year, product used, all impact control horizons.

Q. When is the best time to treat?

Anytime during the seasonal growth period is appropriate. If weed and algae growth are a problem, you can successfully treat. Do not treat before growth appears.

Q. Do we have to treat each year?

Typically, treatment is an annual event, often requiring two applications for season long control. Some waterbodies will yield different plant types growing at different times. Systemic herbicides can achieve longer term control.

Q. Do I need to wear personal protective equipment?

See the label for exact requirements. Generally, long pants ,long sleeves, footwear, gloves and eye wear are specified. The LABEL covers all usage information.

Q. Are the products safe for people, fish, wildlife and pets?

All products on this site are EPA registered for use in the aquatic environment. The products used are effective on plants and algae at very low concentration levels allowing for a large margin of safe use when used according to label directions.

Only two products have swim restrictions – 24 hours – Navigate and Weedtrine-D

Fish Consumption 
There are no fish consumption restrictions with these products.

See individual label for any restrictions.

Pets and Wildlife
There are no water use restrictions for domestic pets or wildlife e.g. ducks, geese, birds or the family dog.

Always refer to the product "LABEL" for exact use information and directions and for any new changes.

Q. Are regulatory permits required?

Many states require a permit for herbicide/algaecide control of weeds and algae in protected waters. Consult your State Fish and Game Agency.

Q. Do U.S. states have aquatic weed issues specific to each state?

Rarely are aquatic weeds confined by state or regional borders. However, we find that certain issues are more common in some states than others. Please visit our state weed control pages for issues common in that state: