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Photo is of parent taxon

Sitka sedge, water sedge

Photo is of parent taxon

calcareous water sedge, carex subétroit

Culms

35–150 cm, angles scabrous.

35–100 cm, angles glabrous or scabrous.

Leaves

basal sheaths leafless, usually red-brown;

blades epistomic, 5–18 mm wide, adaxially papillose.

basal sheaths leafless, usually red-brown;

blades amphistomic, 5–8 mm wide, papillose on both surfaces.

Inflorescences

peduncle of proximal spike to 11 cm;

proximal bract longer than inflorescence, 3–10 mm wide.

peduncle of proximal spike not more than 4 cm;

proximal bract longer than inflorescence, 4–8 mm wide.

Spikes

pendent or the terminal usually erect;

proximal 3–6 spikes pistillate, 4.5–11.5 cm × 4–7 mm, base attenuate;

terminal 2–4 spikes staminate.

erect;

proximal 2–6 spikes pistillate, 4–6 cm × 4–7 mm, base cuneate or attenuate;

terminal 1–3 spikes staminate.

Perigynia

pale brown, ellipsoid, 1.9–3.5 × 1–1.2 mm, apex acute or obtuse;

beak purple-brown, 0.3–0.4 mm, papery.

pale brown, veinless, obovoid, 2.6–3.2 × 1.5–2.2 mm, apex rounded;

beak pale brown, thickened, not more than 0.2 mm.

Pistillate

scales red-brown or purple-brown.

scales pale red-brown with narrow red-brown marginand broad pale midvein.

2n

= 72, 74, 78, 80.

= 76, 77.

Carex aquatilis var. dives

Carex aquatilis var. substricta

Phenology Fruiting Jul–Aug. Fruiting Jul–Aug.
Habitat Marshes, shallow water along shores Marshes, shallow water along shores, usually in neutral or calcareous substrates
Elevation 0–900 m (0–3000 ft) 0–1000 m (0–3300 ft)
Distribution
from FNA
AK; CA; MT; OR; WA; BC
[BONAP county map]
from FNA
CT; IA; IL; IN; KS; MA; ME; MI; MN; MO; ND; NE; NJ; NY; OH; PA; SD; VA; VT; WI; MB; NB; NS; ON; QC
Discussion

Carex aquatilis var. dives is the most robust variety of C. aquatilis and the only member to have pendent spikes, ellipsoid perigynia, and epistomic leaves. Carex aquatilis var. dives intergrades with var. aquatilis and does not appear to be distinct at the specific level. It may hybridize with C. lyngbyei.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Populations of Carex aquatilis var. substricta from Minnesota to Massachusetts tend to have very pale scales with a very broad, pale brown midvein, distinctly obovoid perigynia, and broad pistillate spikes that are rarely staminate at the apex. These populations tend to occur on neutral or calcareous substrates (fens) rather than the more acidic marshes favored by var. aquatilis. The two varieties intergrade where they come into contact.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 23, p. 398. FNA vol. 23, p. 398.
Parent taxa Cyperaceae > Carex > sect. Phacocystis > Carex aquatilis Cyperaceae > Carex > sect. Phacocystis > Carex aquatilis
Sibling taxa
C. aquatilis var. aquatilis, C. aquatilis var. minor, C. aquatilis var. substricta
C. aquatilis var. aquatilis, C. aquatilis var. dives, C. aquatilis var. minor
Synonyms C. dives, C. howellii, C. panda, C. sitchensis C. substricta
Name authority (Holm) Kükenthal: in H. G. A. Engler, Pflanzenr. 28[IV,20]: 311. (1909) Kükenthal: in H. G. A. Engler, Pflanzenr. 38[IV,20]: 309. (1909)
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