No Algae Here!

Pond & Lake Q & A

Q: How do I control floating and bottom-growing algae in my lake? – Tom in New York

A: Whether it’s floating or submerged, algae can turn a lake into a green mess in no time. It’s unsightly, it’s sometimes stinky and in extreme cases, it can cause a fish kill. The good news is that algae can be controlled no matter what time of year. It starts with controlling the population and ends with a long-term management plan.

Before we dive in, it’s important to understand the difference between algae and weeds. The term “algae” refers to a wide range of single and multi-celled organisms that live in the water and metabolize carbon dioxide into oxygen via photosynthesis, just like plants. They differ from plants or weeds in that they don’t have true leaves, roots or stems.

In lakes and ponds, the most common varieties of algae include: Green floating algae that creates a “pea soup” appearance; Chara or Stonewort, which are a bottom-growing, seaweed-looking type that can be mistaken for weeds, and string or filamentous algae, which are actually long strings of algae connected together.

Sometimes, pond and lake owners may mistake duckweed for floating algae, but if you look very closely, you’ll find that it’s actually duckweed or watermeal. Check out this blog entry to learn more about controlling this invasive weed.

Population Check

If your pond is coated in pea soup or the bottom is carpeted in Chara or string algae, you can knock back the population with a chemical herbicide like Algae Defense®. It provides quick results and it’s formulated to get a pond under control – especially during the hot summer months. Do not use if your pond or lake is stocked with koi or goldfish. If your pond has trout, check your carbonate hardness with a water hardness test kit, like the Laguna® Quick Dip Multi-Test Strips, and make sure the carbonate hardness is above 50 parts per million (ppm) before using Algae Defense®.

Long-Term Strategy

Algae Defense® by Pond Logic® will solve a crisis, but to keep your pond or lake looking clean and clear, you’ll need to be proactive and develop a plan to manage the algae. The most successful approach centers on cutting off the algae’s food supply – nutrients.

Nutrients can come from a wide variety of sources, like grass clippings, twigs, trees, fish waste, yard and farm fertilizers and runoff. As these nutrients break down, they produce ammonia, which triggers the nitrogen cycle. Nitrifying bacteria surround the ammonia, turning it into nitrites and then into nitrates (nutrients) – which then feed the algae.

So, how do you reduce the nutrients in your pond?
Try these tips:

That green gunk can be controlled in your pond or lake. It just takes a little planning and some proactive management. When you see the results, it’ll be worth it!

POND TALK: When was your worst algae bloom and how did you control it?

Picture of Phragmites.

Pond & Lake Q & A

Q: How do I control invasive Phragmites in my lake?

A: The common reed, Phragmites australis, may seem innocent enough, but these tall grasses topped with feathery tufts can quickly crowd a farm pond or lake. Native and non-invasive varieties of the plants have thrived in wetlands for centuries throughout the United States, but invasive varieties have taken root on the East Coast, Midwest and Pacific Northwest, and in your lake, creating a nuisance along shorelines.

Phragmites Explained
Growing along streams and ponds, phragmites is a perennial wetland grass that can grow to 6 to 15 feet high. The stems, which are erect, smooth and hollow, may be nearly 1 inch in diameter and are topped with 12-inch-long dense panicles, or purple-brown pyramid-shaped plumes of flowers, that emerge between July and September. Leaves arise from the stem are 10 to 20 inches long and up to 2 inches wide.

The plants propagate mainly via an extensive network of underground rhizomes, or horizontal stems, that produce roots and shoots that grow as deep as 39 inches, with their root systems growing down another 3 feet. Dense above ground and below, stands of these plants crowd out native plants and animals; block shorelines, reducing access for swimming, hunting and fishing; and create fire hazards from dry plant material. But they can be controlled.

Controlling the Common Reed
Once phragmites has invaded your lake or pond, you’ll need to develop a long-term management plan to control the plant. Unfortunately, because the plants spread through their rhizomes, they could be difficult to eradicate entirely. That’s where chemical and mechanical control can help.

Herbicidal Control: First, you can spray an EPA-registered herbicide and surfactant product, like Kraken & Cide-Kick Combo, in the late summer or early fall. Mix 4 ounces of Kraken and 2 ounces of Cide-Kick with 1.5 gallons of water. Pour into pond sprayer (like the Airmax Pond Sprayer) and spray on the plants to completely wet the surface of the leaves. Allow the mixture to absorb into the plant and the root system, the most difficult part of the plant to kill, for one to two weeks.

Mechanical Control: Once the herbicide has had a chance to soak into the phragmites’ root system, you can use a weed cutter to cut at the base of the plants, allowing for easier removal with a pond rake. If
you can control your pond’s or lake’s water line, you can also cut the phragmites 2 to 3 inches below the water surface to cut off the plant’s supply of oxygen and drown the plant. To prevent the accidental
spread of the plant, collect the cut material and bag it before disposing of it.

Plan to repeat this routine several years in a row. Patches may emerge even after regular treatments, but once you’ve wiped out the majority of the phragmites, the plant will be much easier to control. Good luck!

POND TALK: How do you control phragmites in your pond or lake?

Cattails

Pond & Lake Q & A

Q: The cattails in my pond are out of control. How do I control them without disturbing the wildlife? - Richard of Minnesota

A: One of the most common of all aquatic plants, cattails can proliferate if left unchecked. Growing from 3 to 10 feet tall in dense colonies around the margins of ponds and lakes, the plants’ strap-like foliage emerges from large, creeping rhizomes in the muddy bottom in the spring. Soon, the cattail’s foliage and spikes, or the plant’s brown cylindrical flower, grow, eventually spreading its seeds and propagating new plants throughout the lake.

Though they can be a pest, a small controlled area of cattails will provide an ideal habitat for amphibians, insects, birds and fish, as well as helping to prevent erosion. But too many of these plants can create an unappealing look and begin to transform a healthy lake or pond into marshland, and eventually dry land.

Controlling cattails is a simple three-step process: You’ll need to spray a herbicide, cut the cattails down and remove them.

1. Spray: The most common way to control cattails is to apply an EPA-registered herbicide and surfactant product, like the Avocet & Cide-Kick Combo. Read the product labels for proper dosage rates, but to treat a 2,500-square-foot area of cattails, mix 8 ounces of Avocet and 4 ounces of Cide-Kick with 2 gallon of water, pour into pond sprayer (like the Airmax Pond Sprayer) and apply onto the water surface where the cattails are growing. Allow the mixture to absorb into the plant and the root system, the most difficult part of the plant to kill, for one to two weeks.

2. Cut: Once the herbicide has had a chance to soak into the cattail’s root system, the plant will turn brown and become limp. At this point, use an aquatic weed cutter to cut at the base of the plants, allowing for easier removal. If you can control your pond’s or lake’s water line, you can also cut the cattails 2 to 3 inches below the water surface to cut off the plant’s supply of oxygen and drown the plant.

3. Remove: Use a pond and beach rake to remove the cut cattails. You can compost them, burn them or dispose of them at your local green waste disposal site.

To completely eradicate cattails in a pond, this process may need to be repeated several times. Once you have the plants under control, they can make a nice addition to your landscape and encourage wildlife to call your pond or lake home.

POND TALK: How do you control cattails in your pond?

Picture of cattails with a pond in the background.

Pond & Lake Q & A

Q: What do I use to kill the emergent weeds on the shoreline? What sprayer should I purchase? NOTE: My kids swim in pond. – James of Wisconsin

A: At first sight or when controlled properly, cattails and other emergent weeds can add natural beauty, structure for fish and act as a buffer to reduce nutrients and sediment caused by runoff. But, beware! Emergent weeds can take over a pond very quickly if left alone for too long. It is best to pick an area of emergent weeds that you are acceptable with and mark it with boulders or other pieces of landscape. This will allow you to control only the emergent weeds that grow outside your acceptable boundary. There are 3 simple steps to control emergent weeds: 1) Spray… 2) Cut… 3) Repeat…

1.) Spray - Select the best product for the job. Avocet is best at providing long-term control for all types of grasses and cattails while Kraken is best for phragmites and/or purple loosestrife. Both Avocet and Kraken are sprayed directly on to the target plant with a tank sprayer (We suggest using the Airmax Pond Sprayer). This will allow you to control all areas or select areas that you have set aside for this type of growth. Also note: Both Avocet & Kraken have no swimming use restrictions.

2) Cut – Emergent weeds can sometimes have a root base deep within the ground so removing them before they are completely dead will allow them to come back very quickly. Most emergent weeds are best treated when the foliage is around 12″ high. This will allow enough contact for the aquatic herbicide. After a successful treatment, they will turn brown and become limp within 7-14 days. After this occurs, use an Aquatic Weed Cutter to cut the weeds at their base and then simply rake them out with the Pond & Beach Rake.

3) Repeat – Repeat these steps as necessary. In some cases it may take several applications to gain control.