American Water Willow Control: How To Get Rid of American Water Willow

American Water Willow is a flowering perennial plant and is a common pond or lake invader that can get in the way of recreational activities, as well as mess with the aquatic ecosystem.  The American Water Willow has long spear-like leaves with a center vein and can grow up to 3 feet tall and often forms thick clusters on water surfaces that help stabilize shorelines. In some cases American Water Willow is beneficial, but if it's growing and forming a dense cluster in water, you may have a problem if you use the water for recreation.  

American Water Willow has crept up all over the United States, preferring to reside in wetlands like streams, swamps, ponds and rivers. This plant can spread from seeds and can develop multiple rhizomes to form colonies that spread quickly if there is no intervention.

If you have American Water Willow invading your aquatic property, follow our guide below which contains recommendations of products that can eliminate American Water Willow permanently.

Identification

American Water Willow is basically a tree that grows in aquatic areas. Their leaves look very much like those of the willow tree. The leaves are opposite, long and narrowly tapered (up to inches 6 long and ½ inch wide) with smooth margins and a unique-looking midvein that is white. The tree bark of the American Water Willow can be a dark brown or black color that is textured with small ridges.

American Water Willows flower between the months of May and October. The flowers are on long stems that grow from the base of the leaves. The flowers have 5 petals and look similar to orchid being primarily white with streaks of purple and violet on the lower side of the petals. 

Use our description and the image provided to help you to identify whether the weed you see is American water willow. If you need further assistance, you can contact us and we will help you with the correct ID.

Inspection

Where to Inspect

American water willow are found prominently in places where there is lots of water and sunlight. They can also be found in shallow water and mud.

What to Look For

Look for the American Water Willow poking up from out of the water. They can be identified by their long, narrow, leaves which taper off or have toothed edges, similar to that of a willow tree. You may also see the formation of white flowers among the green leaves or, if fully mature, a larger orchid-like flower with purples and pink streaks. If the American Water Willow is in a wildlife area, there may be deer, beavers, muskrats and nutria that will like to consume it so spotting these animals will let you know where it is.

Treatment

Before handling any herbicides, make sure to have on the proper PPE in the form of gloves, glasses and a respirator mask. Our top herbicide recommendation labeled to effectively control American Water Willow is Ecomazapyr 2SL Aquatic herbicide as it is broad-spectrum and works systemically. 

Step 1 - Mix the Ecomazapyr 2SL

Before using Ecomazapyr, you will need to calculate the size of the area to be treated by measuring and multiplying the area length times the width (length x width = square footage). To get acreage, you would need to take the square footage you calculated and divide by 43,560 (Square footage /43,560 = Acreage). For large volume applications using a professional spray rig, apply at 4-6 pints per acre in up to 100 gallons of water.  For small spot treatment applications of Ecomazapyr using a hand sprayer or backpack sprayer, you can mix from a 0.5% concentration at 0.6 fl. oz. up to a 5% concentration a 6.5 fl. oz. in a gallon of water. 

Fill your spray tank with half the required amount of water, add in the appropriate measured amount of Ecomazapyr 2SL and then fill with the remaining amount of water. Agitate the sprayer well to mix the solution. 

Step 2 - Spot Treat American Water Willow

Once water temperatures are around sixty degrees or warmer you should spray the Ecomazapyr mixture. Ideally, this would be in the early morning or late evening when the wind is calm to prevent spray drift into unwanted areas when applying the herbicide mixture. 

Adjust the nozzle on the spray wand to a narrow spray pattern to allow for decent coverage without an over-concentration of the herbicide. Apply the application liberally to the American water willow, but do not apply the herbicide to the point of runoff to reduce the chances of contamination to the water in the area. Depending on the size of the pond or lake, it may be best to apply the herbicide in sections rather than all at once. 

Step 2 - Follow Up Application

Reapplication may be necessary to totally get rid of Water Willow. Total control may be achieved in about 2 weeks but it really depends on the plants persistence. If you don't see a noticeable difference after 2 to 4 days, apply again and once more until the plant has totally died out.

Prevention

To prevent American Water Willow from making a comeback, we suggest applying Vision Pond Dye to your water body. This product is a filtering agent and helps to reduce vegetation growth. Apply at a rate of 1 quart per surface acre of water at a 5-foot average depth. Using the Ecomazapyr 2SL periodically as a preventative measure can also keep American Water Willow from establishing itself again.

Key Takeaways

• American Water Willow is a weed that can form dense colonies that can get interfere with recreation and attract wildlife.
• Ecomazapyr 2SL has proven to do an excellent job in eradicating American Water Willow from water bodies and are our top recommendations.
• Regular monitoring, preventative applications of Ecomazapyr 2SL and adding Vision Pond Dye to your water body are the best tips for American Water Willow prevention.