American Bulrush

The secondary involucral bracts of Schoenoplectus americanus lack blades and closely resemble floral scales, in contrast to S. pungens and S. deltarum. Although mostly very locally distributed, S. americanus is ecologically important in many coastal marshes. In recent years it has seriously declined (e.g., in Maryland and Louisiana). It may occur in southwestern Kansas; I have not seen a specimen. It probably has been extirpated from the Missouri station, based on one collection from 1886 (G. Yatskievych, pers. comm.). The report from New Hampshire is based on M. L. Fernald (1950). The stations on the Maine and Connecticut coasts, at Lake Champlain in Vermont, and in Oklahoma are based on putative S. americanus × S. pungens specimens. Some plants in the southwest are atypical in having nearly flat culm sides and leaf blades to 1.5 times as long as their sheaths as in the type of Scirpus monophyllus J. Presl & C. Presl from Peru. The name Scirpes americanus was long misapplied to Schoenoplectus pungens; Schoenoplectus americanus was known as Scirpus olneyi (A. E. Schuyler 1974).

Rhizomes 2–5 mm diam. Culms sharply trigonous, sides deeply concave throughout to rarely nearly flat, 0.4–2.5 m × 3–10 mm. Leaves ca. 3, basal, less than 1/2 culm length; sheath fronts not pinnate-fibrillose; blades 1–3, V-shaped near base, otherwise laterally flattened-trigonous in cross section; distal blade 0.2–1.5 times as long as sheath, 25–200 × 2–8 mm. Inflorescences capitate or very rarely with 1 branch to 5 mm; proximal bract usually erect, resembling leaf blade, 1–6 cm. Spikelets 2–20, 5–15 × 3–5 mm; scales bright orange- to red- or purple-brown to straw-colored, often partly translucent, usually clearly lineolate-spotted, broadly ovate, 2.7–4 × 2–3 mm, smooth or awn sparsely spinulose, margins deciduously ciliolate, flanks of proximal scale often with several ribs, apex rounded to acute, notch 0.1–0.4 mm deep, awn not contorted, 0.2–0.6 mm. Flowers: perianth members (2–)5–6(–7), yellow-brown, bristlelike, slender to stout, often unequal to equaling 1/2 achene body, retrorsely spinulose; anthers 1.5–3 mm; styles 2-fid or 2-fid and 3-fid. Achenes brown when ripe, thickly plano-convex or unequally biconvex or compressed obtusely trigonous, obovoid, 1.8–2.8 × 1.3–2 mm; beak 0.1–0.3 mm. 2n = 78.

B.C., N.S.; Ala., Ariz., Calif., Conn., Del., Fla., Ga., Idaho, Kans., La., Maine, Md., Mass., Mich., Miss., Mo., Nev., N.H., N.J., N.Mex., N.Y., N.C., Okla., Oreg., R.I., S.C., Tex., Utah, Vt., Va., Wash., Wyo.; Mexico; West Indies (Puerto Rico); Central America; South America.

Fruiting spring–summer (south), summer (north).

Brackish or mineral-rich shores, marshes, fens; 0–2200m.

Scirpus americanus Persoon, Syn. Pl. 1: 68. 1805; S. olneyi A. Gray

More info for the term: marsh

In comparison with marshhay cordgrass, Olney's three-square bulrush's rhizomes are
more deeply buried in the soil. If burned when marsh soils are dry,
Olney's three-square bulrush typically suffers much lower rates of mortality where
these plants grow in mixed stands [12].

More info for the terms: fire exclusion, prescribed fire

The Research Project Summary Vegetative response to fire exclusion and
prescribed fire rotation on 2 Maryland salt marshes provides information on
prescribed fire and postfire response of plant community species, including
Olney's three-square bulrush, that was not available when this species review was written.

Olney's threesquare bulrush
Olney's three-square
Olney bulrush
Olney's tule
three-cornered grass
three-cornered sedge
three square sedge
bayonet rush
chairmaker's bulrush

More info for the term: cover

Olney's three-square bulrush regularly provides good nesting habitat for many
species of rails [28]. In Utah, cover value has been rated as fair for
upland game birds and good for waterfowl, small nongame birds, and small
mammals [7].

More info for the term: culm

Olney's three-square bulrush is a coarse, rhizomatous, perennial sedge.
It has erect, sharply triangular and deeply concave-sided culms growing up to 5
feet in height (1.5 m) [10,21]. It generally bears only a few short
leaves up to about 4 inches long (10 cm) which arise from the lower part
of the culm. The inflorescence consists of a cluster of 5 to 12
sessile, crowded spikelets [28]. Rhizomes are located within 6 inches
(15 cm) of the soil surface [28].

Although Olney's three-square bulrush is sporadically distributed from Nova
Scotia to Washington state and south to South America, it grows primarily along
the Atlantic and Gulf coasts and in arid western states [28].

More info for the terms: fire regime, marsh

Olney's three-square bulrush's rhizomes are sufficiently buried in soil, sometimes
up to 6 inches (15 cm), and are thus well protected from the heat of
fire. Additionally, the plants often grow in shallow water which
further insulates the underground regenerative structures.

Olney's three-square bulrush seedling establishment after fire has not been
reported. However, field studies show that Olney's three-square bulrush seeds
stored in the soil are not injured by marsh fires. Palmisano [19] found
that seeds subjected to marsh fires, whether placed on a moist, but
unsaturated soil surface or buried 1 inch (2.5 cm) below the soil
surface had slightly higher germination rates than seeds not subjected
to fire.

FIRE REGIMES :
Find fire regime information for the plant communities in which this
species may occur by entering the species name in the FEIS home page under
"Find FIRE REGIMES".

More info for the term: marsh

Marshhay cordgrass outcompetes and replaces Olney's three-square bulrush in Gulf
Coast brackish marshes that remain unburned for a few to several years.
In a Louisiana brackish marsh, Olney's three-square bulrush was "weeded out" by
marshhay cordgrass after just 3 years of fire protection [28].
Prescribed burning every 2 or 3 years, however, maintains subclimax
stands of Olney's three-square bulrush [12]. For Louisiana coastal marshes, O'Neil
[18] recommended burning Olney's three-square bulrush stands anytime from October
10 to January 1 when water levels are between 0 and 2 inches (0-5 cm)
above the soil surface.

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More info for the terms: geophyte, helophyte

Geophyte
Helophyte

More info for the terms: fresh, marsh, peat

In coastal regions, Olney's three-square bulrush grows primarily on peat in
brackish tidal marshes, where soil salinities range from 2 to 17 ppt,
and water levels range from -2 to +4 inches (-5 to +10 cm) [11,18].
Inland, it primarily grows in marshes, wet meadows, and playas that are
somewhat alkaline, but also grows in fresh water [6]. In an alkali
meadow in Utah, Olney's three-square bulrush dominated the area surrounding the
water source (a spring), but became rarer farther away from the spring,
and was replaced by inland saltgrass and creeping spikerush as water
depth decreased and salinity increased [26]. At this Utah meadow, soils
under Olney's three-square bulrush stands had higher levels of organic matter and
phosphorus than other marsh plant communities.

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This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):

222 Black cottonwood - willow
235 Cottonwood - willow

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This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):

More info for the term: shrub

FRES29 Sagebrush
FRES30 Desert shrub
FRES38 Plains grasslands
FRES41 Wet grasslands

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This species is known to occur in association with the following plant community types (as classified by Küchler 1964):

K033 Chaparral
K040 Saltbush - greasewood
K041 Creosotebush
K042 Creosotebush - bursage
K049 Tule marshes
K055 Sagebrush steppe
K073 Northern cordgrass prairie
K078 Southern cordgrass prairie
K098 Northern floodplain forest

More info for the term: peat

Only aboveground (or abovewater) plant parts of Olney's three-square bulrush are
removed by fire when water levels are aboveground or only slightly below
the soil surface. Thus the plant survives most fires because perennating
underground organs are not harmed. However, under severe drought conditions,
fire can burn deep into peat layers and kill Olney's three-square bulrush by
charring or consuming the rhizomes .

Olney's three-square bulrush rhizomes are a preferred food of muskrat,
and Canada and snow goose [15,20,28]. It is sometimes an important nutria food
source. Olney's three-square bulrush stands serve as primary wintering grounds for
the snow goose, where this plant makes up about 90 percent of the goose's diet.
Where geese or muskrat populations are high, use by these animals can be so great
that they cause "eat outs"; that is, they destroy large areas of Olney's
three-square bulrush vegetation by consuming all the rootstocks and rhizomes [28].

The seeds are eaten by wintering ducks in the South but generally make
up only a small part of the diet [28].

Deer regularly feed on species of Scirpus. In terms of volume consumed,
Olney's three-square bulrush ranked second among 50 plant species fed to captive
deer in Louisiana [28].

More info for the term: marsh

Olney's three-square bulrush forms nearly monodominant stands in some marshes.
In coastal areas it is most abundant in brackish marshes and is commonly
associated with seashore saltgrass (Distichlis spicata var. spicata),
marshhay cordgrass (Spartina patens), big cordgrass (S. cynosuroides),
smooth cordgrass (S. alterniflora), and saltmarsh bulrush (Scirpus
robustus) [20,28]. In desert regions of the West, Olney's three-square
bulrush often dominates or codominates slightly to moderately saline marshes
bordering lakes or springs. Codominants of western marshes include
creeping spikerush (Eleocharis palustris), Nebraska sedge (Carex
nebraskensis), inland saltgrass (Distichlis spicata var. stricta),
berula (Berula erecta), and marsh yellowcress (Rorippa islandica)
[3,26,32].

Olney's three-square bulrush dominated communities are described in the following
publications:

Aquatic and semiaquatic vegetation of Utah Lake and its bays [3]

Plant ecology of spring-fed salt marshes in western Utah [2]

More info for the term: graminoid

Graminoid

Management and maintenance of Olney's three-square bulrush stands depends
primarily on maintenance of water levels and secondarily on salinity levels.
Maximum survival and growth in coastal areas occur where average minimum
yearly water levels do not fall below 2 to 4 inches (5-10 cm) above the
soil surface [23].

Olney's three-square bulrush increases under light to moderate cattle grazing.
Under heavy grazing, however, it is replaced by less palatable species
such as seashore saltgrass, black rush (Juncus roemerianus), and
seashore paspalum (Paspalum vaginatum) [4,28].

AL AR AZ CA CT DE FL GA ID KS
LA MA MD MI MS NC NH NJ NM NV
NY OH OK OR RI SC TX UT VA WA
NS MEXICO

Olney's three-square bulrush rhizomes are highly palatable to the muskrat, nutria,
Canada goose, and snow goose [28]. In the South, Olney's three-square bulrush is
moderately palatable to cattle. Tender, young shoots are most
attractive [28].

Palatability was rated as follows in Utah: poor for sheep, horses, elk,
mule deer, and pronghorn; fair for cattle, upland game birds, and small
nongame birds; and good for waterfowl and small mammals [7].

More info on this topic.

More info for the term: fruit

In Louisiana, Olney's three-square bulrush begins spring growth in March
when soil temperatures 4 inches (10 cm) below the soil surface reach 60 degrees
Fahrenheit (16 deg C) [11,19]. Culms grow at a uniform rate until
August, but by October, nearly all the culms are dead. A small
percentage of the culms remain green throughout the winter [19].

In Utah, spring growth began on March 27 in marshes near warm springs,
and on April 14 in marshes far-removed from warm water [2].

Flowering and fruit production dates are as follows:

Delaware - flowers from early June to September [28]
New England - flowers from July 20 to August 8 [25]
Louisiana - flowering begins in late March and is finished by late May.
Seeds are ripe by the end of June. Seedfall begins in
mid-July [19].
North and South Carolina - flowers from June to September [21]
Utah - flowers in early May [2]

More info for the terms: culm, density

Olney's three-square bulrush often sprouts within a week of burning [11,12]. In
Louisiana, Olney's three-square bulrush culm density reached or exceeded preburn
density within 4 weeks of burning whether burned in October, December,
or February [5]. Another study in Louisiana similarly found that
burning during different seasons had no effect on Olney's three-square bulrush culm
density [11]. In this study, plants quickly sprouted whether burned in
fall, winter, or spring as long as water levels were even with or
slightly above the soil surface at the time of burning. However,
maximum leaf growth occurred in March and April when soil temperatures
rose above 60 degrees Fahrenheit (16 C), no matter what time of year
plants were burned.

More info for the terms: herb, rhizome

Rhizomatous herb, rhizome in soil

More info for the terms: marsh, natural, seed

Sexual reproduction: Olney's three-square bulrush seed production has been
variously reported as very poor to heavy, with seed yields ranging from
0 to 24 pounds per acre (0-27 kg/ha) [28]. The seeds undergo a long
period of afterripening, often requiring 18 months or more before
germination can occur. The seeds remain dormant as long as they are
submerged in water and thus become a component of the marsh seed bank.
Germination and seedling establishment potentially occur on exposed
mudflats following marsh drawdown, yet seedling establishment under
these natural conditions appears to be rare [19]. Under laboratory
conditions, maximum germination of only 25 percent was achieved in
distilled water under fluctuating temperatures between 68 and 95 degrees
Fahrenheit (20-35 deg C) [20]. Germination decreased with increasing
salinity with a 50 percent reduction at 4 parts per thousand (ppt) and
no germination at above 13 ppt [20].

Vegetative regeneration: Olney's three-square bulrush perennates and
spreads by rhizomes, which is primarily responsible for the maintenance and
expansion of stands.

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This species can be found in the following regions of the western United States (according to the Bureau of Land Management classification of Physiographic Regions of the western United States):

3 Southern Pacific Border
4 Sierra Mountains
5 Columbia Plateau
6 Upper Basin and Range
7 Lower Basin and Range
9 Middle Rocky Mountains
14 Great Plains

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More info for the terms: climax, competition, marsh

Obligate Initial Community Species (Gulf Coast)
Obligate Climax Species (Atlantic Coast and western U.S.)

The successional status of Olney's three-square bulrush varies regionally.
Along the Gulf coast, it is a seral species, and gives way to seashore
saltgrass and marshhay cordgrass in the absence of periodic (every few
years) burning or other disturbance.

In Utah, Olney's three-square bulrush is considered climax. Referring to
Olney's three-square bulrush stands at Fish Springs, Utah, Bolen [2] stated
the "stands contain no other marsh species of comparable status and
are considered to represent closed stands of vegetation. It is
completely successful in its niche and competition from other
communities and/or species was not observed."

Along the East Coast, Olney's three-square bulrush forms climax stands that are
apparently maintained more by the slowly rising sea level than by fire
[28].

Scirpus americanus Pers. [6,10,31]
Scirpus olneyi A. Gray

The currently accepted scientific name of Olney's three-square bulrush is Schoenoplectus
americanus (Pers.) Volk (Cyperaceae) [34,35].

The taxonomy of Olney three-square bulrush is somewhat confusing because of the
consistent misapplication of scientific names within the genus for many
years [24].

Olney's three-square bulrush is used in saltmarsh revegetation programs.
The best place to initiate new stands is probably in brackish areas where
salinities range from 5 to 10 parts per thousand and water depths range
from 0 to 4 inches (0-10 cm) [11]. Stands are best established by
planting rootstocks 4 to 6 inches (10-15 cm) below the soil surface in
winter at a spacing of about 6 by 6 feet (1.8 by 1.8 m). Water depths
need to be maintained at 2 to 4 inches (5-10 cm) above the soil surface
for 3 to 4 weeks after planting but can fluctuate thereafter. Muskrat
and nutria need to be controlled on planted areas because they can
severely reduce planting stock. For a detailed discussion on site
preparation and planting techniques see Sipple [28] and Ross and
Chabreck [23].

Scirpus chilensis Nees & Meyen; Nees, Linnaea 9: 293
1834 (nomen nudum); Nova Acta Acad. Leop.-
Carol. 19suppl.: 93. 1843.
Scirpus Olneyi A. Gray; Engelm. & Gray, Bost. Jour. Nat. Hist. 5: 238. 1845.
Schoenoplectus Olneyi Palla, Bot. Jahrb. 10: 299. 1888.
Scirpus Olneyi var. longisetis Kiikenth.; Urban, Ark. Bot. 22A 17 : 8. 1929.
Scirpus Olneyi f. australis Barros & Osten; Osten, Anal. Mus. Hist. Nat. Montevideo II. 3 : 204. 1931.
Perennial; culms to 1 m. tall, from scaly, black rhizomes; culms sharply triquetrous, the angles somewhat winged, green, smooth; 2-3 sheaths at the base having blades to 1 dm. long, keeled, smooth; involucral bract single, smooth, 1-5 cm. long; spikelets 2-10, 0.5-1.5 mm. long, 4 mm. broad, ovate, mostly very obtuse, pale brown or reddish; scales reddish-brown, glabrous, 3 mm. long, the midrib extending beyond the bidentate apex in a sharp mucro, the margins hyaline and slightly fimbriate; style bifid; bristles retrorsely barbed, 4-6, shorter than the achene; achene 2.5 mm. long, 1.5 mm. broad, light brown, smooth, planoconvex, apiculate.
Type locality : Copiapo, Chile.
Distribution: Coastal eastern North America from Nova Scotia to the West Indies, westward through scattered inland localities to the west coast, where common from central California to Central America; South America.

Scirpus americanus Pers. Syn. PI. 1: 68. 1805
Scirpus triqueter sensu Michx. Fl. Bor. Am. 1: 30. 1803. Not S. triqueler L,. 1753.
Scirpus longispicatus Smyth, Trans. Kansas Acad. 16: 163. 1899.
Schoenoplectus americanus Volkart; Schinz & Keller, Fl. Schweiz ed. 2, 1: 75. 1905.
Scirpus Ohieyi var. contortus Fames, Rhodora 9: 220. 1907.
Helophylax americanus Schiz & Thell. Viert. Nat. Ges. Zurich 53: 587. 1909.
Scirpus solispicatus Lunell, Am. Midi. Nat. 4: 230. 1915.
Perennial; culms mostly ca. 1 m. tall, erect from reddish, scaleless stolons, the roots reddish, fibrous; sheaths commonly as many as 3 at the base, commonly whitish or green, bearing a blade to 2 dm. long which is green, broad, fiat, not scabrous (5 dm. long and 8 mm. broad in unusual specimens); culms trigonous, smooth, green, keeled; involucral bract single, 1.5-12 cm. long, erect, green, trigonous, scabrous on the angles; second bract very rarely present; spikelets reddish, sessile, 1-5, or in occasional specimens to 15, 5-20 mm. long, 4 mm. broad; scales 4 mm. long, 3 mm. broad, the midrib prominent, excurrent from the notched apex of the scale, the smooth or scabrous mucro slightly recurved, glabrous, the margins strongly fimbriate, pale brown, variously flecked with red, somewhat viscid-dotted; style bifid; anther 1.5 mm. long; bristles 4, often tortuous, reddish-brown, about half to equaling the length of the achene, retrorsely barbed; achene 3 mm. long, 2 mm. broad, dark brown, smooth, planoconvex, prominently apiculate.
Type locality: "In Carolina inferiore."
Distribution: Stream banks and lake margins; Nova Scotia, south to Florida, west to Wisconsin and Texas.

Schoenoplectus americanus (syn. Scirpus americanus) is a species of flowering plant in the sedge family known by the common names chairmaker's bulrush and Olney's three-square bulrush. It is native to the Americas, where it is known from Alaska to Nova Scotia and all the way into southern South America; it is most common along the East and Gulf Coasts of the United States and in parts of the western states. It grows in many types of coastal and inland wetland habitat, as well as sagebrush, desert scrub, chaparral, and plains. This rhizomatous perennial herb easily exceeds two meters in height. The stiff stems are sharply three-angled and usually very concave between the edges. Each plant has three or fewer leaves which are short and narrow. The inflorescence is a small head of several spikelets which may be brown to bright orange, red, purplish, or pale and translucent. They have hairy edges. The fruit is a brown achene. The plant reproduces sexually by seed and colonies spread via vegetative reproduction, sprouting from the rhizomes.

This plant, particularly the rhizomes, are a food source of muskrat, nutria, and other animals; it is strongly favored by the snow goose in its wintering grounds.

Native American groups used this plant for many purposes, including food, basketry, and hatmaking. It is used for revegetation projects in salt marsh habitat in its native range. It is a model organism in the study of salt marsh ecology and its response to climate change (currently global warming).