PROTECTING WISCONSIN'S BIODIVERSITY

 
 
   
 
Scientific Name Common Name Global Rank State Rank Federal Status WI Status

Clustered Bur-reed (Sparganium glomeratum)

Spar_glom.jpg

 

 

 

 

9032.jpg

Photo by June Dobberpuhl

 

Counties with Mapped NHI Occurrences

Clustered Bur-reed (Sparganium glomeratum), a Wisconsin Threatened plant, is found in cold ditches and pools within sedge meadows, willow-alder thickets and, occasionally, tamarack stands on the Lake Superior clay plain. Blooming occurs late-June through late-July, fruiting late-July through early-September. The optimal identification period for this species is early-July through early-September.

 
 
 

Clustered bur-reed is an aquatic forb, 2-6dm tall, with stout, floating to erect, stems. It has a simple inflorescence, occasionally with a basal branch. Flowers are unisexual, it has several sessile pistillate heads, 1.5-2cm thick when ripe, staminate head is solitary (or sometimes 2) and abuts pistillate heads below. Achenes have a brown, shiny, fusiform body, 3-4 mm, slightly constricted below the middle, tapering to a straight or slightly curved beak of 1.5-2mm. Leaves are flat or weakly keeled, 3-8mm wide. Bracteal leaves are dilated at the base.

Distinguishing characteristics include its 1-2 staminate heads that abut the upper pistillate head and its shiny achene.

Blooming occurs late-June through late-July, fruiting late-July through early-September.

Perennial. The optimal identification period for this species is early-July through early-September.

Associated species include Salix petiolaris, Alnus rugosa, Calamagrostis canadensis, Cornus stolonifera, Petasites sagittatus, Eleocharis nitida, and Ranunculus gmelinii.

Clustered bur-reed prefers wet soils and is found in cold ditches and pools within sedge meadows, willow-alder thickets and, occasionally, tamarack stands on the Lake Superior clay plain.

Avoid known individual plant locations and conduct operations elsewhere when they are least likely to cause damage. Ideally, this would involve frozen, snow-covered ground. However, in areas of the state where frozen conditions are unreliable, very dry soils late in the growing season might be the best available alternative. Consult with a biologist, if needed.

Avoid broadcast spraying of herbicides and use care with spot spraying.

Minimize disturbance to hydrology, including soil disturbance from rutting.

Survey for and control invasive plants prior to conducting timber operations, as these can be spread by vehicles and often respond vigorously to increased light. See forestry BMPs for invasive species.

Species of Greatest Conservation Need (SGCN) are associated with habitats (or natural communities) and places on the landscape. Understanding relationships among SGCN, natural communities and ecological landscapes help us make decisions about issues affecting SGCN and their habitat and how to respond. Download the Wildlife Action Plan association score spreadsheet to explore rare species, natural communities and ecological landscape associations

Conservation actions respond to issues or threats, which adversely affect species of greatest conservation need (SGCN) or their habitats. Besides actions such as restoring wetlands or planting resilient tree species in northern communities, research, surveys and monitoring are also among conservation actions described in the Wisconsin Wildlife Action Plan because lack of information can threaten our ability to successfully preserve and care for natural resources.