• Archives

  • Categories

  • Pages

What chemical should I use to treat water milfoil? | Ponds & Lakes Q&A

What chemical should I use to treat water milfoil?

Q: What chemical should I use to treat water milfoil?

Douglas – Goddard, KS

A: Before we dive into how to treat this aquatic invader, let’s get to know it a little better first.

Water milfoil, also known as Eurasian Water Milfoil (Myriophyllum spicatum), is a submersed aquatic plant that’s native to Europe, Asia and northern Africa. It has feather-like leaves that grow from white, red or brown stems, and some species produce four-petaled pink or reddish flowers that rise a few inches from the water’s surface.

Eurasian water milfoil thrives on fertile, fine-textured, inorganic sediments. An opportunistic species, the plant prefers water bodies that receive nitrogen and phosphorous-laden runoff, like a farm or agricultural pond. Growth explodes when water temperatures rise, which promote multiple periods of flowing and fragmentation (or when pieces of the plant grow roots and develop new plants).

If left unchecked, water milfoil can dominate a pond or lake in no time.

Controlling Growth

The good news is that you can find myriad products to manage this invasive species. The chemical you choose has to do with several factors.

Closed or open system? If your pond is mostly covered with water milfoil, does not have water flowing in and out, and is not used for irrigation, NovaSource™ WhiteCap® SC Aquatic Herbicide will be your best choice. The product uses the active ingredient fluridone, which effectively controls a wide range of floating, submerged and emergent aquatic vegetation including duckweed, hydrilla, bladderwort, naiad, elodea, water lily, coontail, pondweed and water milfoil – giving you more herbicide bang for your buck.

Small area or large? If you’re treating a smaller area of a pond or lake, Pond Logic® PondWeed Defense® Aquatic Herbicide works like a charm. It’s a rapid-acting contact herbicide that drops aquatic weeds below the water surface in four to seven days, though heavy growth may require a second application in 10 to 12 weeks.

Spray or granular? If you prefer granular herbicides to spray ones and have a smaller area to treat, choose Navigate. This granular herbicide is ideal for spot-treating weeds around docks, beach areas and shorelines, killing the roots of both submerged and floating plants, including water milfoil, coontail and water lilies. You’ll see it go to work within 10 days; you’ll see full effects in three to five weeks.

Plant, Human Considerations

When choosing a chemical herbicide, pay special attention to use restrictions. Some of these products have limitations for use in irrigation ponds, swimming holes and other situations until the chemical has adequately broken down in the water.

Also consider the other critters – plants, fish and animals – that live in your pond. Certain products can harm game fish, koi or goldfish, and can kill off prize water lilies and other welcome aquatic plants.

Pond Talk: How do you manage invasive plants in your pond or lake?

WhiteCap Fluridone Aquatic Herbicide - One Treatment Lasts All Season

I Know That Floating Plants Help Shade My Pond, But What Do Submerged Plants Do? | Decorative Ponds & Water Gardens Q & A

I know that floating plants help shade my pond, but what do submerged plants do?

Q: I know that floating plants help shade my pond, but what do submerged plants do?

Donnita – Palos Park, IL

A: Got plants? If you’re like most pond hobbyists, you probably have plenty of growing and blooming greenery surrounding your water garden – but what about sub-surface varieties? Underwater plants, like hornwort, and red stemmed parrots feather, offer great benefits to your water feature and its inhabitants, including:

Filtration: Underwater plants naturally filter your water. How? Plants, with their copious amounts of surface area on their leaves, stems and roots, absorb nitrates and fish waste – which is actually fertilizer to them. The result is a body of water that’s cleaner and clearer, thanks to Mother Nature’s nitrogen cycle.

Predator Protection: Sub-surface plants also give your fish and other pond critters places to hide when predators stalk or attack. Koi and goldfish will swim into the lush growth and hide out when a raccoon stops by the pond or a blue heron circles overhead. The greenery provides excellent camouflage for your finned friends.

Aesthetic Appeal: As popular as they may be, gravel-bottom ponds are boring. And they’re not very natural-looking either. Have you ever seen a wild pond or lake with no plants beneath the surface? Nope, didn’t think so. Ponds planted with below-the-waterline foliage create a more realistic-looking – and aesthetically pleasing – water feature, which is something most (if not all!) hobbyists hope to achieve.

Oxygen: Underwater plants are called “oxygenators” for a reason. They naturally produce oxygen as a byproduct of photosynthesis – and oxygen is one of the best things for your pond’s health and vitality. When submerged plants are used in combination with a sub-surface aeration system, you’ll wind up with cleaner water that truly supports your pond’s inhabitants.

Spawning Areas: The leaves, stems and root systems of underwater plants give your pond life safe places to spawn and lay their eggs. And when those tiny fry hatch, the plants provide protection, food and a comfy place to call home.

Submerged plants are easy to add to your water garden or fish pond. Simply fill planting baskets, like the Laguna Submersible Pond Planting Baskets, with planting media, add some oxygenators, and place the planted basket on the bottom of your pond or on a plant shelf on the side of your pond. The planting baskets allow the plant’s roots to branch out and find nourishment while containing it and preventing fish from nibbling on its root system.

Add some plants to your pond today. Your fish will thank you for them!

Pond Talk: Do you have submerged plants in your pond?

Create Oxygen For Your Plants - Hornwort Submerged Plants

Follow

Get every new post delivered to your Inbox.

Join 123 other followers