Wisconsin Aquatic Weed Control and Management in Ponds and Lakes

Below are some descriptions of and solutions for Wisconsin aquatic weed control issues.

Purple Loosestrife

Purple loosestrife is a nuisance exotic weed that is extremely invasive in Wisconsin’s wetlands as it displaces native wetland vegetation and degrades wildlife habitat. And as native vegetation is displaced, rare plants are often the first species to disappear. This undesirable plant prevents many desirable native wetland plants from becoming established. It grows from 3-7 feet tall with a dense bushy growth of 1-50 stems. Flowers vary from purple to magenta, possess 5-6 petals aggregated into numerous long spikes, and bloom from July to September.

Purple loosestrife was first introduced as a garden perennial from Europe during the 1800’s. The plant was first detected in Wisconsin in the early 1930’s and has been recorded in 70 of Wisconsin’s 72 counties. Purple loosestrife spreads mainly by seed, but it can also spread vegetatively from root or stem segments. A single stalk can produce from 100,000 to 300,000 seeds a year. The absence of natural predators also contributes to its proliferation in North America.

For removing Purple Loosestrife from your Wisconsin lake or pond, Lake Restoration recommends an Open Water Kit.

Reed Canary Grass

Reed Canary Grass is a very important aquatic weed in Wisconsin and nearby states, and its control is especially difficult. It ranked #1 in importance in IPAW’s survey of invasive plants. Reed Canary Grass can grow on dry soils in upland habitats and in the partial shade of oak woodlands, but does best on fertile, moist organic soils in full sun. It is a major problem in natural wetlands, including marshes, wet prairies, sedge meadows, fens, stream banks, and seasonally wet areas. It also grows in disturbed areas such as bergs and spoil piles. Areas invaded by reed canary grass may be of little use to wildlife and aids in the displacement of desirable native plants.

RCG can reproduce vegetatively by its rhizomes and rhizome fragments, as well as sexually by its abundantly produced seed. Most plants and recurring populations develop from rhizomes. Seeds can be dispersed in animal fur, on human clothing or on automobiles. The most common vector for the seeds and rhizome fragments however, is probably dispersal by water. Established populations can survive prolonged drought and can survive over one year of flooding, especially if parts of the plant are not submerged.

We recommend using the Open Water Kit for controlling Reed Canary Grass in your Wisconsin Lake.

Curlyleaf Pondweed

This plant is native to Africa, Australia, and Eurasia and was accidentally introduced in the United States in the 1800’s. By the 1930’s it was well established in the midwest and is now in all but 2 of the lower 48 states.

Curlyleaf pondweed is a submersed aquatic plant with oblong, wavy, blue-green leaves that attach to its stems in an alternate pattern. Leaves can be up to 3 inches long and a half inch wide. Curlyleaf pondweed produces small flowers that are arranged on dense terminal spikes that rise a few inches above the surface of the water. This plant can tolerate extreme conditions including low light and cold water temperatures and has even been found growing under 20 inches of snow covered ice.

Curlyleaf pondweed is usually introduced to new bodies of water through the transport of plant fragments on aquatic equipment like boats and trailers. Curlyleaf’s dense growth can reduce the opportunity for water recreational activities and can decrease values of properties on lakes with a heavy infestation of the weed. We recommend using RestoreAccess Ultra to control the invasion of this aquatic weed.

Eurasian Watermilfoil

Eurasian watermilfoil can grow in a wide variety of habitats and conditions: ponds, lakes, reservoirs, and slow flowing rivers and streams. It will grow in shallow or deep water and does well in waters that have had some sort of disturbance like intense plant management, overabundance of nutrients, or extensive motorboat use.

This Wisconsin aquatic weed is a submersed perennial with a long underwater stem that branches profusely at the surface of the water. The plants leaves are whorled (opposite) on the stem at each node with four feather-like leaves per whorl. It produces small reddish flowers that emerge several inches above the water on a spike grown from the tip of the stem. Eurasian watermilfoil reproduces by seed and vegetative means quickly contributing to issues in Wisconsin’s aquatic weed control.

Use treatments once plants are established but before flowering occurs.

RestoreAccess Ultra is perfect for this weed’s control in Wisconsin ponds and lakes.