Russet Sedge

Foodplant / saprobe
sporodochium of Arthrinium dematiaceous anamorph of Arthrinium puccinioides is saprobic on often dry, bleached, dead leaf of Carex saxatilis
Remarks: season: (1-)3-5(-12)

Carex saxatilis is highly variable in North America. Plants from western North America, often named C. physocarpa, tend to be robust with long peduncles on the pistillate spikes, wide leaves, and large perigynia. These characters decrease in size eastward across North America with successively smaller plants usually referred to as C. saxatilis and C. miliaris. This weak east/west cline is confounded by large amounts of variation within small geographic areas and phenotypic plasticity. B. A. Ford et al. (1991) and B. A. Ford and P. W. Ball (1992) have demonstrated that these segregates represent elements in a continuum rather than discrete taxa.

Hybrids between Carex saxatilis and C. vesicaria (= C. ×stenolepis Lessing; = C. ×mainensis Porter ex Britton) and C. saxatilis and C. utriculata (= C. ×physocarpoides Lepage) have been found in North America (B. A. Ford et al. 1993). These hybrids are infrequent, largely sterile, and intermediate in morphology between the two parents.

Plants usually loosely cespitose; rhizomes short, congested. Culms trigonous in cross section, 8–90 cm, scabrous distally. Leaves: basal sheaths reddish brown; ligules as wide as to slightly longer than wide; blades mid to dark green, V-shaped, sometimes with revolute margins, 0.9–6.3 mm wide, glabrous. Inflorescences 2.5–14(–20) cm; proximal bract 0.6–16(–29) cm, shorter than or equaling inflorescence; proximal 1–3 spikes pistillate, erect or the proximal often pendent; terminal 1–3 spikes staminate. Pistillate scales ovate, 1.9–4.3(–5) × 0.9–2.1 mm, as long as or shorter than perigynia, margins entire, apex obtuse or acute, awnless. Perigynia ascending, often dark-colored, obscurely few-veined, veins not running to beak, tightly investing achene, elliptic, 2.2–5.5 × 1.1–2.9 mm, apex abruptly contracted; beak 0.2–0.8 mm, bidentulate, teeth straight, to 0.3 mm. Stigmas 2. Achenes yellow, biconvex, smooth. 2n = 78, 80.

Greenland; St. Pierre and Miquelon; Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., N.S., Nunavut, Ont., Que., Sask., Yukon; Alaska, Colo., Maine, Mont., Utah, Wash., Wyo.; Eurasia.

Fruiting summer.

Fens, bogs, wet tundra, roadside ditches, shores of lakes, ponds, and slow moving streams, often in shallow water; 0–3700m.

Carex ambusta Boott; C. compacta R. Brown ex Dewey; C. miliaris Michaux; C. physocarpa C. Presl; C. rhomalea (Fernald) Mackenzie

Carex miliaris Michx. Fl. Bor. Am. 2: 174. 1803
"Carex pulla Gooden." A. Gray, Man. ed. 5. 602. 1867.
Carex pulla var. (?) miliaris A. Gray, Man. ed. 5. 602. 1867. (Based on C. miliaris Michx.)
Carex miliaris var. Olney, Caric. Bor. -Am. 12. 1872. (From Moosehead Lake, Maine.)
Carex saxatilis var. (?) miliaris L. H. Bailey, Bot. Gaz. 9: 120. 1884. (Based on C. miliaris Michx.)
Carex miliaris var. obtusa L. H. Bailey, Mem. Torrey .Club 1 : 36. 1889. (Type from Marguerite
River, lower Canada.) Carex miliaris var. major L. H. Bailey, Mem. Torrey Club 1 : 36. 1889. (Based on C. miliaris var.
Olney.) "Carex rotundata Wahl." Fernald, Rhodora 3: 49. 1901. (As to Maine plant.) "Carex saxatilis L." Fernald, Rhodora 3: 50. 1901. (As to Mt. Katahdin plant.) Carex saxatilis var. rhomalea Fernald, Rhodora 3: 50. 1901. (Based on C. miliaris var. major
Bailey.) Carex miliaris f. major "L. H. Bailey" Kiikenth. in Engler, Pflanzenreich 4 2 °: 719. 1909. (Based on
C. miliaris var. major L. H. Bailey.) Carex rhomalea Mackenzie, Bull. Torrey Club 37: 246. 1910. (Based on C. saxatilis var. rhomalea
Fernald.)
Rootstocks long-creeping, slender, tough, the culms arising one to several together, slender but stiff and rather wiry, 2-8 dm. high, shorter than to exceeding the leaves, phyllopodic, sharply triangular, smooth or slightly roughened above, purplish-red-tinged at base, the basal sheaths breaking and becoming somewhat filamentose, the dried-up leaves of the previous year conspicuous; leaves with well-developed blades usually 4-6 to a fertile culm, on the lower fourth, sparingly septate-nodulose, the blades light-green, stiff, involute, or almost filiform, usually 1-2 dm. long, 1-3 mm. wide towards the base, much narrower above, smooth, except at apex; sterile-culm leaves longer and rougher; sheaths tight, hyaline ventrally, often yellowish-brown-tinged, concave at mouth, the ligule about as wide as long or wider than long, rounded or retuse at apex; staminate spike solitary (or often with a smaller sessile one at its base), slender-peduncled, narrowly linear, 1-4 cm. long, 2-3 mm. wide, the peduncle nearly smooth or roughish, the scales oblong-obovate, obtuse, light-brown to dark-brown with lighter midrib and white-hyaline margins; pistillate spikes usually 2, more or less strongly separate, erect, sessile or short-peduncled, the peduncles varying from much shorter than to about three fourths as long as the spikes, the spikes linearto oblong-cylindric, or even suborbicular, 0.5-2 cm. long, 4-7 mm. wide, densely flowered, containing 15-40 appressed to ascending-spreading perigynia in several rows; lower bract leaf -like, narrowly dark-tinged and auricled at base, sheathless or very nearly so, usually exceeding the inflorescence but sometimes shorter; upper bract much reduced; scales ovate, dark-brown to light-brown with conspicuous lighter midrib and very narrow hyaline margins, as wide below as the perigynia and varying from cuspidate or short-acuminate and slightly longer than the perigynia (the lower) to obtusish or acute and shorter than the perigynia (the upper) ; perigynia ovoid, plano-convex or unequally biconvex, 2.5-3.5 mm. long, 2 mm. wide, not inflated at maturity, 2-edged, smooth, shining, membranaceous, puncticulate, dull-greenish-yellow or brownish-tinged, flat or slightly convex and nerveless ventrally, obscurely few-nerved and convex dorsally, round-truncate at base and sessile, abruptly minutely beaked, the beak 0.5 mm. long, brownish-tinged, entire or emarginate or minutely toothed, achenes lenticular, obovoid, 2-2.5 mm. long, 1.5-1.75 mm. wide, closely enveloped and occupying all of the body of the perigynium, yellowish, puncticulate, sessile, contracted or tapering into and continuous with the slender, persistent, rather short, strongly bent style, at maturity bent downward against the achene ; stigmas 2, blackish, slender.
Type locality: "Hab. in paludosis borealibus Canadae, praesertim ad lacus Mistassins dictos." Distribution: Borders of lakes and streams and moist banks, calcareous districts, Labrador and Newfoundland, southward to Quebec and central Maine. Very variable in size. (Specimens examined from Labrador, Newfoundland, Quebec, including Anticosti, New Brunswick, Maine.)

Carex saxatilis L. Sp. PI. 976. 1753
Carex pulla Gooden. Trans. Linn. Soc. 3 : 78. pi. 14. 1797. ("Habitat in montibus Scoticis.")
Carex fusca Schkuhr, Riedgr. 64. pi. Cc,f. 88. 1801. (Type from Scandinavia.) Not C. fusca All.
Carex snilla Feldman, Bull. Soc. Nat. Mosc. 8: 285. 1835. (Type from Russia.)
Carex pulla a picea Drejer, Nat. Tidssk. 3: 474. 1841. (Type from Iceland.)
Carex pulla & fusca Drejer, Nat. Tidssk. 3: 474. 1841. (Type from Iceland.)
Carex vesicaria subsp. pulla Anderss. Cyp. Scand. 19. 1849. (Based on C. pulla Gooden.)
Carex pulla var. polystachya Blytt, Norges Fl. 212. 1861. (Type from Norway.)
Carex pulla var. laxa Trautv. Acta Hort. Petrop. 5 : 130. 1877. (Type from northern Siberia.)
Carex pulla f. pedunculata Kjellm. Vega-Exp. Vet. Iaktt. 1: 560. 1882. (Type from northern
Siberia.) Carex pulla var. sibirica Christ; Scheutz, Sv. Vet.-Akad. Handl. II. 22'°: 181. 1888. (Type from
northern Siberia.) Carex vesicaria subsp. saxatilis "L. " Kiikenth. in Engler, Pflanzenreich 4 20 : 728. 1909. (Based on
C. saxatilis L.) Carex vesicaria subsp. saxatilis f. polystachya "Blytt" Kiikenth. in Engler, Pflanzenreich 4 2 °: 728.
1909. (Based on C. pulla var. polystachya Blytt.) Carex vesicaria subsp. saxatilis f. laxa "Trautv." Kiikenth. in Engler, Pflanzenreich 4 2 °: 728. 1909.
(Based on C. pulla var. laxa Trautv.) Carex pulla f. debilis Porsild, Medd. Gronland 50: 370. 1912. (Type from Greenland.)
Culms arising one or few together from slender, horizontal, long-creeping rootstocks, 1-7 dm. high, stiff, erect, exceeding or exceeded by the leaves, aphyllopodic, triangular, from nearly smooth to strongly roughened above, brownish-tinged at base, the lower sheaths not filamentose, the dried-up leaves of the previous year conspicuous; leaves with well-developed blades 3-7 to a fertile culm, clustered on the lower third, somewhat septate-nodulose, the blades dullgreen, thickish, stiff, ascending or spreading, flat, or somewhat channeled at base, 0.5-3 dm. long, 2-4.5 mm. wide, attenuate, roughened towards the tip, the sheaths hyaline ventrally, prolonged upward beyond base of blade, the ligule very short; staminate spike solitary (or often with an additional sessile one at its base), peduncled, linear-subclavate, usually 1-2.5 cm. long, 2-3 mm. wide, the peduncle roughish, the scales oblong-obovate, obtusish or acutish, purplish-black or brownish-black with lighter midrib and narrow white-hyaline apex and upper margins; pistillate spikes 1 or 2, strongly separate or more rarely aggregated, the upper nearly sessile and erect, the lower shortto long-peduncled, sometimes nodding, typically shortoblong, varying from suborbicular to oblong-cylindric, 8-25 mm. long, 6-9 mm. wide, densely flowered, heavy, containing 15-50 ascending or ascending-spreading perigynia in several to many rows; lowest bract leaflet-like, shorter than or exceeding the inflorescence, not sheathing but often conspicuously dark-tinged at base ; upper bracts much reduced ; scales ovate or ovatelanceolate, obtuse to acute, purplishor brownish-black with lighter midrib and white-hyaline margins and apex, narrower than and from one half to nearly as long as the perigynia; perigynia ovoid, 3-4 mm. long, 1.75-2.25 mm. wide, suborbicular in cross-section, moderately inflated, membranaceous, smooth, shining, puncticulate, brownish or rarely straw-colored at maturity, nerveless or nearly so ventrally, obscurely few-nerved dorsally, rounded at base and substipitate, abruptly very short-beaked, the beak 0.5 mm. long, emarginate or shallowly bidentate; achenes lenticular, suborbicular, 1.75-2 mm. long, 1.5-1.75 mm. wide, nearly filling lower half of perigynium, nearly sessile, contracted into and continuous with the slender, persistent, more or less strongly bent style ; stigmas 2, slender, whitish, rather long.
Type locality: "Habitat in Europae alpibus."
Distribution: Greenland and Labrador; widely distributed in arctic Eurasia. (Specimens examined from Greenland, Labrador.)

Carex saxatilis is a species of sedge known by the common names rock sedge and russet sedge.