Hardstem Bulrush

Hardstem Bulrush
Photo courtesy of Richard J. Shaw, Intermountain Herbarium.
©Intermountain Herbarium

Common Name(s):

Hardstem Bulrush
Tule

Scientific Name:

Schoenoplectus acutus (Muhl. ex Bigelow) A. & D. Löve

Scientific Name Synonyms:

Scirpus acutus Muhl. ex Bigelow
Scirpus lacustris L. p.p.
Schoenoplectus lacustris (L) Palla ssp. acutus (Muhl. ex Bigelow) A. & D. Löve

Symbol:

SCAC3

Description:

Life Span: Perennial

Origin: Native

Season: N/A

Growth Characteristics: Hardstem bulrush is a robustly rhizomatous obligate wetland plant which forms dense colonies. It reproduces by seed which is dispersed by wind and water. It establishes well from seed stored in the seedbank. Hardstem bulrush seed establishes and germinates best on moist, bare soil, but will germinate submerged in up to 1.6 inches of water in the laboratory. Hardstem bulrush reproduces vegetatively from rhizomes.

Seedhead: The flowering parts are compact and umbellate with a greenish bract extended, simulating a continuation of the stem (culm). Spikelets are usually numerous, grayish or gray-brown, 1/4 - 5/8 inch long. They can be solitary or 2 to several. Sepals and petals have bristles or scales. Fruit is three-sided.

Leaves: Leaves are reduced to basal sheaths with blades up to 3.2 inches long.

Stems:  Stems are slender and erect, usually 3-10 feet (1-3 m) tall, but occasionally reaching heights of 16.5 feet (5 m).

Ecological Adaptions:

Hardstem bulrush often forms monocultures in marshes throughout its range. Hardstem bulrush grows best on sites with saturated soil or standing water for most of the year. It occurs in marshes, swamps, seeps, washes, floodplains, along lake and stream margins, and in wet meadows. It grows in fresh or brackish water. Hardstem bulrush can grow in areas where the water table is up to 5 feet (1.5 m) above or 0.33 feet (0.1 m) below the soil surface. It is fairly drought tolerant; it can persist through several years of dry conditions. In Utah, Hardstem bulrush is found at elevations of 3620 to 8800 feet.

Soils: Soils are usually coarse-fine textured, anaerobic soils and has a high tolerance for salinity.

Associated Species: In Utah hardstem bulrush is commonly associated with saltmarsh bulrush, alkali bulrush, saltgrass, common reed, and sago pondweed.

Uses and Management:

Hardstem bulrush is an important aquatic or semiaquatic species. It provides cover for numerous birds and mammals. It is a staple food for muskrat and other small mammals. Seeds are eaten by passerines and waterfowl. It provides valuable nesting cover and escape cover for a variety of passerines and waterfowl throughout its range. In Utah hardstem bulrush is important heron and egret nesting cover.

It regrows well after removal and is tolerant of fire. It spread rapidly by stolons. It is considered a problem species in some circles because it can be an aggressively invasive plant that closes in bare shorelines and open water in marshes important for production of some waterfowl and shorebirds.

Hardstem bulrush herbage production is high, but forage value is low. It is seldom grazed by livestock if other forage is available. If upland forage becomes limited and soil conditions dry, livestock and big game animals may utilize hardstem bulrush. It buffers wind and wave action on lakes and ponds, which may enhance the establishment of vegetation along shorelines.

Consumption of hardstem bulrush by waterfowl and muskrats may decrease aboveground standing biomass. It may be replaced by cattail (Typha spp.) in continuously flooded marshes following drawdown. However, during years of drought coupled with heavy livestock grazing, it may increase at the expense of cattail.

Hardstem bulrush is used in artificial wetlands to filter agricultural wastewater.