Aquatic Invasive Species

Current Efforts

The Upper Sugar River Watershed Association has completed an Aquatic Invasive Species (AIS) Strategic Plan for 2014-2018.  This will be helpful in giving our organization and our partners direction in eradicating and fighting the spread of AIS in the Upper Sugar River Watershed.

Read the strategic plan here: USRWA AIS Strategic Plan 2014 – 2018

Chart of native plant species in the Sugar River: Sugar River native vegetation list

In 2014, USRWA plans to fight the spread of invasive species in the watershed through a number ways:

– Install and maintain two wader wash stations to prevent the spread of New Zealand mudsnails

– Educate and train volunteers in monitoring for New Zealand mudsnails and use kick-net sampling for NZM in four locations in the Upper Sugar River Watershed

– Monitor 10 new sites for invasive species in partnership with Project RED

– Control Phragmites along Badger Mill Creek

– Begin a biological control project using beetles to manage Purple Loosestrife in the Lake Belle View area. Learn more about our efforts from our video courtesy of Wisconsin Sea Grant:

Past Accomplishments

2013: USRWA completed a full assessment of the Sugar River from Verona to Belleville using GPS waypoints to track populations of invasive and native plant species along the river banks.  This study also incorporated areas of exposed and eroded soil, which will be layered into a map along with soil types and areas of extreme slope to locate potentially problematic places along the river.  This assessment allowed USRWA to create a five-year strategic plan including current threats to the Upper Sugar River Watershed, proposed management strategies and fact sheets of aquatic invasive species of concern.  USRWA also worked with the Ice Age Trail Alliance to remove Phragmites at a half-acre site along Badger Mill Creek.

2012: In the summer of 2012 the USRWA coupled aquatic invasive species monitoring efforts with their existing volunteer stream-monitoring program and collaborated with other local groups to meet several goals:

-Fostered awareness and stewardship within the Upper Sugar River Watershed of the effects of invasive species on rivers;

-Collected aquatic invasive species data for the Upper Sugar River and report findings to the Surface Waters Integrated Monitoring System (SWIMS) database;

-Collaborated with local teachers to conduct outreach and education projects within local K-12 schools;

-Promoted responsible recreation on the Sugar River and Lake Belle View.

This project will rely heavily on volunteers from the community – people like you! Potential tasks include river monitoring and reporting, community outreach, volunteer recruiting, restoration work days for students and teachers and signage posting and maintenance.

2011: In the fall of 2011, the USRWA was awarded a grant from the Wisconsin Department of Natural Resources to monitor and prevent the spread of aquatic invasive species, and to educate the public about the detrimental effects of those species in Wisconsin’s river corridors.  Aquatic plants such as Eurasian watermilfoil, Curly-leaf pondweed, Japanese knotweed and Purple loosestrife, as well as Mosquitofish are among the worst offenders in the Upper Sugar River area.

Problem Species Within the Upper Sugar River Corridor

Phragmites australis: 

phragmites australis

The Ice Age Trail Alliance is working to eradicate a patch of phragmites near the Badger Mill Creek. Phragmites australis is a clonal grass species with woody hollow culms which can grow up to six meters in height. Leaves are lanceolate, often 20-40cm long and 1-4cm wide. Flowers develop by mid summer and are arranged in tawny spikelets with many tufts of silky hair. This grass is wind pollinated but self-incompatible. Seed set is highly variable and occurs through fall and winter and may be important in colonization of new areas. Germination occurs in spring on exposed moist soils. Vegetative spread by below-ground rhizomes can result in dense clones.

Phragmites australis control:

USRWA worked in conjunction with the Ice Age Trail Alliance in the fall of 2013 to control Phragmites australis at a half-acre site located between the Ice Age Trail and the Badger Mill Creek in the City of Verona.  Previous efforts by Ice Age Trail Alliance volunteers entailed utilizing the “cut and bundle” method. This method involves tying bundles of Phragmites at the base with a biodegradable twine, cutting the bundle of stalks at the base, and then treating the remaining stalks with “Habitat” herbicide.  The upper portion of the Phragmites bundle was transported to a nearby dumping site off of the trail.  USRWA volunteers joined Ice Age Trail Alliance volunteers in the next phase of the control plan; the “glove of death” technique.  Volunteers wore long rubber gloves with a cotton glove worn over top of the rubber one. Dabbing the cotton glove with “Habitat” herbicide and moving the glove upward from the base of the plant causes the plant to incorporate the herbicide and translocate it to the plant’s root system.  Because Phragmites reproduces via rhizomes, this method will be effective even if volunteers failed to treat every individual plant at the infested site.

photo 1 (1) photo 2 (1) photo 2 w ed










On October 30, 2013 a crew of six volunteers re-visited the site to rake up the remaining stalks to expose the mineral soil for subsequent re-seeding with native vegetation.  Dead stalks were hauled to the same site where plant matter from the “cut and bundle” phase was disposed of.

Grant funds from USRWA’s Aquatic Invasive Species Planning/Education/Prevention grant were coupled with funds from the New Century School’s Wisconsin Environmental Education Board grant to purchase $300.00 worth of native seed.

Students from Mr. Lee Lohr’s 5th grade class at the New Century School visited the site on November 15, 2013 to spread the seed mix and participate in a lesson plan focused on the importance of biodiversity, native species, and invasive species.

Reed canary grass (Phalaris arundinacea):









This invasive grass species is so widespread throughout the Sugar River corridor that we have not included it in our interactive web mapping application. 



Appearance: Perennial coarse cool season grass that grows 2 – 6′ high. It had been especially selected for its vigor, and is one of the first to sprout in spring. Erect hairless stems.

Leaf blades: 1⁄4″-1⁄3″ wide, gradually tapering, up to 10″ long. It has a highly transparent ligule (a membrane where blade and sheath meet) which distinguishes it from the native bluejoint grass.

Flowers: Densely clustered single florets, green to purple changing to beige over time, blooms May to mid-June.

Roots: Reproduces vegetatively through horizontal stems growing below the soil surface, called rhizomes, creating a thick impenetrable mat at or directly below the soil surface.

Other notes on reed canary grass:

– Reed canary is a major threat to natural wetlands. It out competes most native species.

– It presents a major challenge in wetland mitigation efforts.

– It forms large, single-species stands, with which other species cannot compete.

– If cut during the growing season a second growth spurt occurs in the fall.

– Invasion is associated with disturbances, such as ditch building, stream channeling sedimentation and intentional planting.

Japanese knotweed (Polygonum cupsidatum):

japaense knotweed

River Alliance’s Project RED (Riverine Early Detectors) found a stand of Japanese knotweed along the Sugar River near Frenchtown Road. This is a herbaceous perennial plant with hollow stems and lacy greenish-white flowers. It grows in large clones from 5-10 feet tall and reproduces primarily via rhizomes. Japanese knotweed emerges in early spring, flowers in late summer, and dies off in fall/winter. The stalks remain upright until new growth the following spring.

Japanese knotweed is an escaped ornamental that is becoming increasingly common along stream corridors and rights-of-way in Wisconsin. The species forms dense stands that crowd out all other vegetation, degrading native plant and animal habitat. This perennial plant is difficult to control because it has extremely vigorous rhizomes that form a deep, dense mat. In addition, the plant can resprout from fragments; along streams, plant parts may fall into the water to create new infestations downstream.

Curly-leaf pondweed (Potamogeton crispus):  


This prolific aquatic invasive species has been found in various locations in the Upper Sugar River. Leaves are somewhat stiff and crinkled, approximately 1/2-inch wide and 2 to 3 inches long; leaves are arranged alternately around the stem, and become more dense toward the end of branches; produces winter buds can be confused with claspingleaf pondweed.

Hints to identify: The plant has small “teeth” visible along edge of leaf; begins growing in early spring before most other pondweeds; dies back during midsummer; the flower stalks, when present, stick up above the water surface in June; appears reddish-brown in the water, but is actually green when pulled out of the water and examined closely. Easily confused with claspingleaf pondweed, which has leaves with no “teeth” around their edges.

Management strategy: Like Eurasian watermilfoil, curly-leaf pondweed is not native to the United States and often causes problems due to excessive growth. When control is necessary, herbicides and harvesting can be effective. 

Eurasian watermilfoil (Myriophyllum spicatum):

EWMEurasian watermilfoil was accidentally introduced to North America from Europe. The species spread westward into inland lakes primarily by boats and also by waterbirds; it reached Midwestern states between the 1950s and 1980s. In nutrient-rich lakes and rivers it can form thick underwater stands of tangled stems and vast mats of vegetation at the water’s surface. In shallow areas the plant can interfere with water recreation such as boating, fishing, and swimming. The plant’s floating canopy can also crowd out important native water plants.

A key factor in the plant’s success is its ability to reproduce through stem fragmentation and runners. A single segment of stem and leaves can take root and form a new colony. Fragments clinging to boats and trailers can spread the plant from lake to lake. The mechanical clearing of aquatic plants for beaches, docks, and landings creates thousands of new stem fragments. Removing native vegetation creates perfect habitat for invading Eurasian watermilfoil.

Eurasian watermilfoil has difficulty becoming established in lakes and rivers with well established populations of native plants. In some lakes the plant appears to coexist with native flora and has little impact on fish and other aquatic animals.

Likely means of spread: Eurasian watermilfoil may become entangled in boat propellers, or may attach to keels and rudders of sailboat. Stems can become lodged among any watercraft apparatus or sports equipment that moves through the water, especially boat trailers.

How to identify: Eurasian watermilfoil typically has 12 to 21 pairs of leaflets. The native northern watermilfoil, with which it is often confused, usually has 5 to 9 pairs.

Purple loosetrife (Lythrum salicaria):

PLSeveral PL plants have been located in the wetland area adjacent to Lake Belle View at the terminus of the Upper Sugar River Watershed. Purple loosestrife is a wetland plant from Europe and Asia. It was introduced into the east coast of North America in the 1800s. The species first spreading along roads, canals, and drainage ditches, then later distributed as an ornamental, this exotic plant is in 40 states and all Canadian border provinces.

Purple loosestrife invades marshes and lakeshores, replacing cattails and other wetland plants. The plant can form dense, impenetrable stands which are unsuitable as cover, food, or nesting sites for a wide range of native wetland animals including ducks, geese, rails, bitterns, muskrats, frogs, toads, and turtles. Many rare and endangered wetland plants and animals are also at risk.

Do not be fooled… Purple Loosetrife Look-alikes!


Thanks to the Wisconsin and Minnesota DNR for providing information used in this article.

What about the natives? Check out our Sugar River native vegetation information sheet, and feel free to email us with additions!

Sugar River native vegetation list