Schoenoplectus deltarum

(Schuyler) Soják

Cas. Nár. Mus., Odd. Prír. 141: 62. 1972.

Common names: Delta bulrush
IllustratedEndemic
Basionym: Scirpus deltarum Schuyler Notul. Nat. Acad. Nat. Sci. Philadelphia 427: 1, figs. 2, 4, 6, 7. 1970
Treatment appears in FNA Volume 23. Treatment on page 52. Mentioned on page 46, 51.

Rhizomes 2–6 mm diam.; scales much shorter than internodes, disintegrating to fibers. Culms sharply trigonous, sides convex to flat near base, concave distally, 0.7–2.3 m × 2.5–6 mm, smooth. Leaves 3–5, basal; sheath fronts not pinnate-fibrillose; blades 2–3, proximally V-shaped, distally trigonous to asymmetrically laterally flattened in cross-section, angles distally scabridulous; distal blade 1–1.5 times as long as sheath, 9–30 cm × 2–7 mm. Inflorescences capitate or rarely with 1–2 branches to 5 mm; proximal bract usually erect, resembling leaf-blade, trigonous proximally, (1–) 3–20 cm. Spikelets 3–35, 6–15 × 4–5 mm; scales bright orangebrown or partly purplish, ovate, 3.5–5.5 × 2–3 mm, smooth or awn sparsely spinulose, margins deciduously ciliolate, flanks of proximal scale sometimes with a few ribs, midrib prominent, apex acute, notch 0.6–1 mm deep, awn irregularly bent, 1–1.5 mm. Flowers: perianth members 3–6, orangebrown, bristlelike, very slender, some equaling achene, some often rudimentary, retrorsely spinulose; anthers 2–3 mm; styles 2-fid. Achenes brown, unequally biconvex, obovoid to obpyriform, 1.9–2.6 × 1.3–1.7 mm; beak 0.1–0.3 mm. 2n = 78.


Phenology: Fruiting late spring–summer.
Habitat: Brackish, coastal shores, marshes, ditches, waste places
Elevation: 0–100 m

Distribution

V23 72-distribution-map.jpg

Ala., Fla., Kans., La., Miss., Mo., Tex.

Discussion

Robust plants of Schoenoplectus deltarum are very distinct because of their many large spikelets; less robust plants closely resemble S. pungens. As Schoenoplectus deltarum combines some characteristics of S. americanus with most characteristics of S. pungens, it may be of hybrid origin. Intermediates between these species occur along the coast from North Carolina to Florida. Schoenoplectus deltarum is often dominant in much of the marsh on mudflats formed in the Mississippi River delta, and it is a major food of geese wintering there.

Selected References

None.

Lower Taxa

None.

"prolonged" is not a number.

... more about "Schoenoplectus deltarum"
0.19 cm1.9 mm <br />0.0019 m <br /> (0.26 cm2.6 mm <br />0.0026 m <br />) +
with transverse wavy ridges +  and rugose +
obovoid;obpyriform +
1.3mm;1.7mm +
scabridulous +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
S. Galen Smith +
(Schuyler) Soják +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
shortened +
deciduous +
enlarged +
Scirpus deltarum +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
rudimentary +
2 (?) +  and 3 (?) +
distally trigonous +  and asymmetrically laterally flattened +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
ascending +  and appressed +
parallel +  and divergent +
terete +, rolled +  and plicate +
Delta bulrush +
dorsiventrally flat +  and c-shaped or laterally compressed +
2mm +  and 10mm +
trigonous +
9 cm90 mm <br />0.09 m <br /> (30 cm300 mm <br />0.3 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
Ala. +, Fla. +, Kans. +, La. +, Miss. +, Mo. +  and Tex. +
0–100 m +
hypogynous +  and subtending +
biconvex +  and trigonous +
Brackish, coastal shores, marshes, ditches, waste places +
1-3 times branched or capitate or of 1 spikelet +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
cauline +  and basal +
membranous +
curved +  and straight +
with (1-)3-6(-30) bristles and/or scales +
Fruiting late spring–summer. +
2-3(-4)-carpellate +
3 (?) +  and 1 (?) +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
3 cm30 mm <br />0.03 m <br /> (20 cm200 mm <br />0.2 m <br />) +
Cas. Nár. Mus., Odd. Prír. +
0.2 cm2 mm <br />0.002 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
adventitious +
purplish +  and bright orangebrown +
disintegrating +
deciduous +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
basal +  and proximal +
2mm;3mm +
not pinnate-fibrillose +
70 cm700 mm <br />0.7 m <br /> (230 cm2,300 mm <br />2.3 m <br />) +
concave +, convex +  and flat +
0.25 cm2.5 mm <br />0.0025 m <br /> (?) +  and 0.6 cm6 mm <br />0.006 m <br /> (?) +
Illustrated +  and Endemic +
0.6 cm6 mm <br />0.006 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
3 +  and 35 +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
Schoenoplectus deltarum +
Schoenoplectus sect. Schoenoplectus +
species +
not +  and rhizomatous +