Ron Wilson

Bog Bulrush

Schoenoplectus mucronatus (L.) Palla
Cyperaceae (Sedge family)

Origin: Africa, Eurasia

Background
Also called ricemarsh bulrush, ricefield bulrush and rough-seed bulrush, bog bulrush was collected before 1900 in New Brunswick and New Jersey. In recent times it has also been reported from New York, Pennsylvania, Illinois, Iowa, Kentucky, Missouri, Tennessee, Maryland and Delaware. It is an important ricefield weed in California, where it was first observed in 1942. It was first observed in the Midwest in 1971. Schoenoplectus mucronatus is cultivated for wildlife food in Washington State.

Distribution and Habitat
Bog bulrush occurs in wet soil and is emergent in fresh water, ponds, and ditches. It has colonized several wetland restoration areas in the mid-Atlantic.

Ecological Threat
This species invades habitats that have been degraded in some way and is not currently known to invade high quality natural wetlands.

Description and Biology

• Plant: annual or perennial sedge with fibrous roots.
• Leaves: triangular in cross-section, arising from the base of the plant.
• Flowers, fruit and seeds: flowers are near the top of the leaf and are brownish, scaly or spiky, carried near the end of a long stem with a distinctive angled bract.
• Spreads: seeds are eaten by waterfowl and probably carried between sites on their feet and feathers.
• Look-alikes: Schoenoplectus fluviatilis and S. purshianus, both native river bulrushes, and other native Schoenoplectus species (various bulrushes and three-square) lack the combination of hair-like projections from the base of the mature seed that are longer than the seed and the nearly right-angled upper bract.

Prevention and Control
Mature seeds may be present anytime from June through October, depending on local conditions. If present, clip and bag the seed heads. Power wash any equipment when moving between sites to remove seeds. Manual and chemical methods are available and effective. For light infestations young plants can be hand-pulled, removing the roots as much as possible. For larger infestations of established plants with significant root masses, it is more effective to treat with a systemic herbicide such as glyphosate (see Control Options).