Carex pachystachya Cham. ex Steud.
Species Image Gallery
(opens in a new window)
 
TAXONOMY
 
Family: Cyperaceae
Genus: Carex
 
Species Synonyms: Carex pyrophila Gandog.
Carex pachystachya var. gracilis (Onley) Mackenzie
Carex pachystachya var. monds-coulteri L. kelso
Carex multimoda Bailey
Carex macloviana ssp. pachystachya (Cham. ex Steud.) Hultén
Carex macloviana var. pachystachya (Cham. ex Steud.) Kükenth.
Carex festiva var. gracilis Olney
Carex festiva var. pachystachya (Cham. ex Steud.)Bailey
Common Names: thickhead sedge
chamisso sedge
thick-spike sedge
 
DISTRIBUTION
 
Canada: southern Yukon Territory – Mackenzie District – British Columbia – Saskatchewan, Ungava – Labrador, eastern Quebec
Saskatchewan: central to southern Saskatchewan; North Battleford – Qu’Appelle River Valley
Ecoregion: Cypress Upland, Aspen Parkland, Boreal Transition, Mid-Boreal Upland, Mid-Boreal Lowland
 
HABITAT
 
Saskatchewan: moist sedge fens, open and treed bogs, wet springy areas
 
RARITY STATUS
 
Provincial Status According
to Harms (2003):
Vulnerable
Nature Conservancy Status:
G5 S3
Saskatchewan Species at
Risk Status:
None
COSEWIC Status:
None
 
Carex pachystachya is vulnerable in Saskatchewan because it is uncommon. This species occurs in only a few localities in the southern and central parts of the province. No immediate threats for this species are known at the present time.
 
SPECIES DESCRIPTION
 
Height: 15 – 120 cm
Roots: rootstocks short
Culms: densely caespitose, exceeding leaves, conspicuously striate
Leaves: well-developed, 3 – 4 per fertile culm, 10 – 30 cm long, 2 – 4 mm wide, flat; sheaths white hyaline or green-veined; ligules 1 – 2.5 mm
Inflorescence: head 1 – 2.5 cm long, dense or open; spikes 4 – 12, crowded
Spike Bracts: scale-like, lowest may be awned, shorter than inflorescence
Spikes: gynaecandrous, ovoid; scales ovate, about width of perigynia, copper-coloured or brown, midrib pale or green, margin scarcely hyaline
Perigynia: ascending to spreading, 3.5 – 5 mm long, ovate, planoconvex, sometimes filled with pithy tissue near base, 2 – 9-nerved abaxially, copper-coloured or brown to blackish, serrulate to middle, occasionally white wing-margined
Beaks: half length or perigynia body, reddish-brown to black at tip, occasionally white hyaline, not winged
Stigmas: 2
Achenes: lenticular, elliptic to broadly ovate
 
CAREX KEY FOR SPECIES FOUND IN SASKATCHEWAN
* The reader is also referred to Carex in Saskatchewan by J. Hudson (1977) and Flora of Alberta edited by J. Packer (1983).
   
1 Leaves mostly basal; spike one per culm, terminal; flowers attached to main stem
2
1 Cauline leaves usually present; spikes usually two or more per culm, terminal and/or lateral; flowers may not all be attached to main stem
11
   
2 Stigmas 2; achenes lenticular
3
2 Stigmas 3; achenes trigonous
5
   
3 Rhizome long, slender; culms solitary or few; spikes unisexual, plant dioecious
C. gynocrates
3 Rhizomes slender or obliquely ascending, if slender, stolons present; culms caespitose; spikes bisexual, androgynous or gynaecandrous
4
   
4 Plant caespitose with rootstocks obliquely ascending; spikes bisexual, androgynous
C. capitata ssp. capitata
4 Plant caespitose with slender rhizomes and stolons; spikes bisexual, gynaecandrous
C. mackenziei
   
5 Plant dioecious; perigynia somewhat pubescent; not caespitose
C. scirpoidea
5 Plant monoecious, androgynous; perigynia may or may not be pubescent, if pubescent, plant caespitose
5
   
6 Pistillate scales deciduous, scale-like; perigynia short-stipitate, spreading or reflexed
C. pauciflora
6 Pistillate scales persistent, scale-like or leaf-like; perigynia sessile, not spreading or reflexed
7
   
7 Pistillate scales green, foliaceous
8
7 Pistillate scales stramineus, brownish or green, scale-like
9
   
8 Perigynium 4 – 6 mm long; beak 2 – 3 mm long
C. backii
8 Perigynium ~ 4 mm long; beak ~ 1 mm long
C. saximontana
   
9 Perigynia beakless, many nerved, apex rounded
C. leptalea
9 Perigynia beaked, few nerved, apex not rounded
10
   
10 Perigynia coriaceous, shining; rhizome long; prairie species
C. obtusata
10 Perigynia puberulent, dull; rhizome short or absent, plant caespitose; dry grasslands
C. filifolia
   
11 Stigmas 2; achenes lenticular
12
11 Stigmas 3; achenes trigonous
65
   
12 At least some of the lateral spikes stalked
13
12 Lateral spikes all sessile
21
   
13 Perigynia 3 – 5.5 mm long, lustrous, inflated, prominently ribbed; beak tubular; style continuous with achene
C. saxatilis
[* C. physocarpioides (C. saxatilis x C. utricularia. Infrequent, sterile. With intermediate characteristics.]
13 Perigynia 2 – 3 (4) mm long, not inflated or lustrous, may be ribbed; beakless; style jointed or continuous with achene or deciduous
14
   
14 Bract at base of inflorescence distinctly sheathing; staminate spike 1; perigynia subterete, rounded at tip
15
14 Bract at base of inflorescence nearly sheathless; staminate spikes 1 or more; perigynia biconvex, sometimes flattened, acute at tip
17
   
15 Lowest bracts as long as or shorter than inflorescence, short-sheathing, may have auricles; scales purplish-black
C. bicolor
15 Lowest bract leaf-like, as long as or longer than inflorescence, long-sheathing, auricles lacking; scales various colours
16
   
16 Perigynia whitish, dry, ribbed, crowded in spike; scales reddish-brown to purplish
C. garberi
16 Perigynia golden-yellow to brown, fleshy, ribbed, not crowded in spike; scales whitish to orangish-brown
C. aurea
   
17 Plant caespitose; rhizomes lacking; leaves 1 – 3 mm wide; perigynia distinctly nerved
C. lenticularis var. lenticularis
17 Plant not caespitose; rhizomes present; leaves 2 – 8 mm wide; perigynia nerved or nerveless
18
   
18 Perigynia 0 – 50 nerved on each face, somewhat inflated, short papillose
C. paleacea
18 Perigynia nerveless, puncticulate or punctate
19
   
19 Pistillate scales acute; achenes indented on one side near middle
C. subspathacea
19 Pistillate scales obtuse to acute to awned; achenes not indented
20
   
20 Lowest bract leaf-like, equal to or longer than inflorescence
C. aquatilis
20 Lowest bract setaceous, shorter than inflorescence
C. bigelowii
   
21 Culms single or loosely tufted (few together) from rhizomes or decumbent stems
22
21 Culms densely tufted; rhizomes short
29
 
22 Culms decumbent, branching, long prostrate stems with erect flowering branches in axils of dried up leaves; sphagnum bogs
C. chordorriza
22 Culms erect or ascending; habitats various
23
 
23 Plants usually dioecious, spikes either completely staminate or pistillate
24
23 Plants monoecious, spikes gynaecandrous or androgynous
26
   
24 Culms obtusely triangular; slender brownish, scaly rhizomes; plants of dry habitats
C. douglasii
24 Culms sharply triangular; rhizomes stout or slender; plants of wet habitats
25
 
25 Perigynia brown, biconvex; rhizomes slender, brown; calcareous bogs; rare
C. simulata
25 Perigynia becoming blackish, planoconvex; rhizomes thick, black; moist prairies and sloughs; common
C. praegracilis
 
26 Spikes in more or less spherical heads, appearing like one spike; high northern latitudes
C. maritima
26 Spikes densely aggregated but not in spherical heads, distinct; distribution various
27
 
27 Perigynia wing-margined, beak markedly bidentate; terminal spike gynaecandrous, middle staminate, lower pistillate
C. siccata
27 Perigynia not wing-margined, beak not markedly bidentate; spikes androgynous
28
 
28 Upper leaf sheaths green; two darks warts present at junction of leaf blade and sheath
C. sartwellii
28 Upper leaf sheaths green; two darks warts present at junction of leaf blade and sheath
C. duriuscula
 
29 Spikes androgynous
30
29 At least upper spikes gynaecandrous, lateral spikes may be pistillate
39
 
30 Spikes few-flowered, with 2 – 3 perigynia and 1 – 2 staminate flowers
C. disperma
30 Spikes with numerous flowers
31
 
31 Spikes 4 – 10, no more than one spike per rachis node; sheaths not red-dotted
32
31 Spikes numerous, rachis nodes may have 2 or more spikes; sheath often red-dotted ventrally or copper-tinged
35
 
32 Leaves < 2 mm wide; spikes widely spaced, in linear arrangement; pistillate scales short-awned
C. hookerana
32 Leaves > 2 mm wide; spikes bunched into orbicular or ovoid arrangement; pistillate scales not awned (may be short-awned in C. gravida)
33
 
33 Arrangement of spikes spherical or orbicular; Cypress Hills
C. hoodii
33 Arrangement of spikes ovoid, at least 2 x as long as broad; southern Saskatchewan
34
 
34 Culms markedly triangular, not wing-margined
C. gravida var. gravida
34 Culms becoming flattened in drying, wing-margined
C. alopecoidea
 
35 Sheaths loose; culms soft and spongy; perigynia spongy and corky
36
35 Sheaths tight; culms slender and firm; perigynia firm
37
 
36 Perigynia ovate, at most only slightly surpassing scales; leaves 2 – 6 mm wide
C. alopecoidea
36 Perigynia triangular, surpassing the scales; leaves 4 – 10 mm wide
C. stipata var. stipata
 
37 Pistillate scales awned; perigynia yellowish or stramineus, blackish in age; leaf sheaths cross-wrinkled
C. vulpinoidea var. vulpinoidea
37 Pistillate scales acuminate; perigynia brownish or black; leaf sheaths not cross wrinkled
38
 
38 Leaf sheath copper-tinged at summit; perigynia brownish, planoconvex
C. prairea
38 Leaf sheath red-dotted; perigynia blackish, biconvex
C. diandra
 
39 Perigynia narrowly or broadly winged, not thickened at base; beak present, usually bidentate; achene narrower than perigynium
40
39 Perigynia at most thin-edged, thickened at base; beak, if present, bidentate or not; achene more than half as wide as perigynium
45
 
40 Bracts leaf-like OR clearly surpassing the spikes; spikes aggregated into a terminal head-like cluster
41
40 Bracts not leaf-like, shorter than spikes; spikes aggregated into lateral and terminal clusters
42
 
41 Bracts leaf-like; pistillate scales greenish-white; culms smooth
C. syncocephala
41 Bracts clearly surpassing the spikes but not leaf-like; pistillate scales reddish-brown and copper-margined; culms roughened below the head
C. athrostachya
 
42 Perigynia subulate, < 1 mm wide
C. crawfordii
42 Perigynia lanceolate, elliptic, ovate, or orbicular, > 1 mm wide
43
 
43 Perigynia concealed by pistillate scales or nearly so
44
43 Perigynia not concealed by narrower or shorter pistillate scales
49
 
44 Perigynia beak flattened and markedly serrulate to tip, bidentate
45
44 Perigynia beak nearly terete, if serrulate, only slightly so, not markedly bidentate
48
 
45 Inflorescence moniliform
46
45 Inflorescence not moniliform, spikes aggregated or approximate
47
 
46 Pistillate scales larger than or equal to perigynia; leaf sheaths tight
C. foena var. foena
46 Pistillate scales smaller than perigynia; leaf sheaths weak
C. projecta
 
47 Scales pale or silvery, appressed; spikes approximate
C. xerantica
47 Scales brown, ascending; spikes aggregated
C. adusta
 
48 Perigynium 6 – 8 mm long, elliptic
C. petasata
48 Perigynium 4 – 6 mm long, ovate
C. pratincola
 
49 Perigynium narrowly lanceolate
C. scoparia
49 Perigynium ovate, elliptic, or orbicular
50
 
50 Beak of perigynium terete and only slightly serrulate
51
50 Beak of perigynium flattened and serrulate to tip
52
 
51 Perigynia reddish to dark coppery-brown
C. pachystachya
51 Perigynia stramineus or light green to brown
C. microptera
 
52 Perigynium 4 – 6 mm long, suborbicular, coriaceous
C. brevior
52 Perigynium 3 – 4 mm long, ovate membranaceous
53
 
53 Spikes distant, inflorescence moniliform; perigynia stramineus at maturity; leaves 1 – 3 mm wide
C. tenera
53 Spikes closely aggregated; perigynia brown at maturity; leaves 2 – 6 mm wide
54
 
54 Perigynia wing-margined to base; leaves < 4 mm wide
C. bebbii
54 Perigynia wing-margined, but reduced at base; leaves > 4 mm wide
C. cristatella
 
55 Perigynia thin-edged, not puncticulate, spreading or reflexed
56
55 Perigynia with rounded margins, puncticulate or not, ascending
58
 
56 Perigynium beak < 1/3 overall perigynium length; pistillate scales shorter than perigynium body
C. interior
56 Perigynium beak > 1/3 overall perigynium length; pistillate scales longer than perigynium body
57
 
57 Perigynia obscurely nerved or nerveless ventrally
C. echinata
57 Perigynia lightly to strongly nerved on both faces
C. sterilis
 
58 Perigynia > 4 mm long, not puncticulate; beak long, bidentate; achene occupying 1/2 to 1/3 or perigynium
C. deweyana
58 Perigynia < 4 mm long, white puncticulate; beak short or absent; achene filling body or perigynium
59
 
59 Lowest bract exceeding inflorescence by several times; spikes 1 – 5-flowered; perigynia 3 – 4 mm long
C. trisperma
59 Bracts absent or lowest bract shorter than inflorescence; spikes several flowered; perigynia < 3 mm long
60
 
60 Perigynia beakless; scales silvery to white hyaline; slender stolons present
61
60 Perigynia short-beaked; scales greenish or brownish to stramineus or rusty; stolons absent
62
 
61 Spikes 2 – 4, aggregated; perigynia faintly nerved
C. tenuiflora
61 Spikes 3 – 5, remote; perigynia strongly nerved or ribbed
C. loliacea
 
62 Perigynia ovate, beak serrulate; spikes 6 – many
C. arcta
62 Perigynia broadest near middle, beak smooth to moderately serrulate; spikes 2 – 9
63
 
63 Spikes 3 – 4, spherical, more or less overlapping; scales reddish
C. heleonastes
63 Spikes 4 or more, conical or ellipsoidal, inflorescence interrupted, only upper spikes overlapping if at all; scales greenish to stramineus
64
 
64 Plants green; spikes 5 – 15 flowered; woodland species
C. brunnescens
64 Plants glaucous; spikes 15 – 30 flowered; bog species
C. canescens ssp. canescens
 
65 Perigynia beak markedly toothed, teeth conspicuous, usually bidentate
66
65 Perigynia beakless or beaked, beak if present, without conspicuous teeth
86
 
66 Perigynia pubescent or puberulent; style jointed with achene
67
66 Perigynia glabrous; style jointed or continuous with achene
76
 
67 Achenes with convex sides; lower bracts shorter than or equal to inflorescence
68
67 Achenes with flat sides; lower bracts longer than inflorescence
74
 
68 Pubescence on perigynia reduced to one line of hairs on each side of the two ribs
C. tonsa var. tonsa
68 Perigynia distinctly pubescent
69
 
69 Pistillate spikes all cauline; culms all elongate
70
69 Some pistillate spikes short-stalked at the base of the plant; culms of various lengths
72
 
70 Staminate spike 10 – 20 mm long; perigynium body spherical; scales about as long as perigynium; dry prairies
C. inops ssp. heliophila
70 Staminate spike 2 – 10 mm long; perigynium body ellipsoid to fusiform to obovoid; scales shorter than perigynium, usually about up to base of beak; woodlands
71
 
71 Perigynia > 3 mm long; scales with white sides; staminate spike 5 – 10 mm long; culms 15 – 30 cm tall
C. peckii
71 Perigynia < 3 mm long; scales with purple sides; staminate spike 2 – 5 mm long; culms 5 – 15 cm tall
C. deflexa
 
72 Bracts of cauline pistillate spikes poorly developed; remnants of old leaves stiff and shredded
C. umbellata
72 Bracts of cauline pistillate spikes well developed; remnants of old leaves soft and only slightly shredded if at all
73
 
73 Rhizomes slender; leaves soft and thin; staminate spike 2 – 5 mm long, nearly sessile
C. deflexa
73 Rhizomes stout; leaves thin but firm; staminate spike 3 – 15 mm long, stalked
C. rossii
 
74 Culms 1 – 3; perigynia finely pubescent, 5 – 7 mm long, conspicuously nerved; dry habitats
C. houghtoniana
74 Culms many, bunched; perigynia densely pubescent, 3 – 5 mm long, nerves obscured by pubescence; damp or aquatic habitats
75
 
75 Leaves filiform-convolute, < 2 mm wide; old leaf sheaths persistent at base of stem
C. lasiocarpa var. americana
75 Leaves flat, 2 – 5 mm wide; old leaf sheaths absent
C. pellita
 
76 Style entirely deciduous from achene, no part persistent; leaves not septate nodulose
C. sprengellii
76 Style not withering to base, lower part of style persisting as a “prong”; leaves usually septate nodulose
77
 
77 Perigynia subulate; pistillate spikes spherical; northern latitudes
C. michauxiana
77 Perigynia lanceolate to ovate; pistillate spikes longer than broad; distribution varies
78
 
78 Perigynia leathery, not lustrous; scarcely inflated
79
78 Perigynia membranous, thin, lustrous or not; usually inflated
82
 
79 Pistillate scales with a short narrow body and a long scabrous awn; wet woodland species
C. pseudocyperus
79 Pistillate scales acute to acuminate, the body visible; large water sedges
80
 
80 Leaves pilose beneath, sheaths pilose; teeth or perigynium beak prominent, 1.5 – 3 mm long, divergent
C. atherodes
80 Leaves and sheaths glabrous; teeth of perigynium beak short, < 1.5 mm long, nearly straight
81
 
81 Perigynia teeth 1 – 1.5 mm long; large sedge, culm 60 – 150 cm tall
C. lacustris
81 Perigynia teeth < 1 mm long; average-sized sedge, culm 30 – 80 cm tall
C. laeviconica
 
82 Perigynia 12 – 25 nerved, not lustrous
C. hystericina
82 Perigynia 7 – 9 nerved, lustrous
83
 
83 Lower perigynia reflexed; lower bracts exceeding inflorescence by at least 2 x; spikes approximate
C. retrorsa
83 Lower perigynia ascending to spreading; lower bracts exceeding inflorescence, but by < 2 x; spikes often distant
84
 
84 Rhizomes absent; perigynia ascending at maturity, 6 – 8-ranked
C. vesicaria var. raeana
84 Rhizomes present; perigynia spreading at maturity, 8 – 12 or more ranked
85
 
85 Culms 40 – 70 cm tall; leaves 2 – 6 mm wide; pistillate spikes densely 50 – 125 flowered
C. rostrata
85 Culms 50 – 80 cm tall; leaves 4 – 8 mm wide; pistillate spikes densely 100 – 200 flowered
C. utricularia
 
86 Perigynia pubescent or puberulent
87
86 Perigynia glabrous
95
 
87 Pistillate spikes loosely flowered; perigynia narrowly lanceolate
C. assiniboinensis
87 Pistillate spikes densely flowered; perigynia ovate or elliptic
88
 
88 Perigynia terete; pistillate bracts sheathless
89
88 Perigynia obtusely triangular; pistillate bracts long-sheathing
93
 
89 Pistillate spikes all cauline; culms all elongate
90
89 Some pistillate spikes short-stalked at the base of the plant; culms of various lengths
91
 
90 Perigynia > 3 mm long; scales with white sides; staminate spike 5 – 10 mm long; culms 15 – 30 cm tall
C. peckii
90 Perigynia < 3 mm long; scales with purple sides; staminate spike 2 – 5 mm long; culms 5 – 15 cm tall
C. deflexa
 
91 Bracts of cauline pistillate spikes poorly developed; remnants of old leaves stiff and shredded
C. umbellata
91 Bracts of cauline pistillate spikes well developed; remnants of old leaves soft and only slightly shredded if at all
92
 
92 Rhizomes slender; leaves soft and thin; staminate spike 2 – 5 mm long, nearly sessile
C. deflexa
92 Rhizomes stout; leaves thin but firm; staminate spike 3 – 15 mm long, stalked
C. rossii
 
93 Terminal spike androgynous, lower spikes on long capillary peduncles; pistillate scales awned
C. pedunculata
93 Terminal spike staminate, lower (pistillate) spikes sessile or short-stalked; pistillate scales blunt-tipped
94
 
94 Staminate spike < 6 mm long, sessile; perigynia 2-ribbed with several nerves; stigma short
C. cocinna
94 Staminate spike to 2 cm long, short-stalked; perigynia 2-ribbed but otherwise nerveless; stigma long
C. richardsonii
 
95 Leaves and sheaths pubescent; perigynia glabrous but appearing felty and conspicuously 15 – 25-nerved
C. torreyi
95 Leaves and sheaths glabrous; perigynia otherwise
96
 
96 Leaf sheath > 3 mm long
97
96 Leaf sheath < 3 mm long or sheathless
105
 
97 Leaves filiform; bracts bladeless but sheathing
C. eburnea
97 Leaves > 0.5 mm wide; bracts with well developed blades
98
 
98 Pistillate spikes elongate, < 4 mm wide, on capillary peduncles; plants tufted
C. capillaries
98 Pistillate spikes short, > 4 mm wide, on short peduncles; plants tufted or rhizomatous
99
 
99 Plants tufted; perigynia conspicuously nerved
100
99 Plants rhizomatous; perigynia obscurely nerved, if at all
102
 
100 Spikes nearly sessile, closely bunched; perigynia 6 – 14-nerved
C. viridula ssp. viridula
100 Spikes peduncled, the lower distant; perigynia 15 – 30-nerved
101
 
101 Perigynia sharply triangular, narrowed at base to stipe; beak at right angles to perigynia
C. leptonervia
101 Perigynia nearly terete, rounded at base, stipe absent; beak straight, very small
C. granularis var. haleana
 
102 Perigynium body widest below middle, rounded at base
C. crawei
102 Perigynium body widest at or above middle and tapering to acute base
103
 
103 Perigynia beaked, beak toothless; foliage deep green
C. vaginata
103 Perigynia beakless; foliage glaucous or gray-green
104
 
104 Leaves glaucous, < 3.5 mm wide, soon folded or involute; northern bog species
C. livida
104 Leaves gray-green, 2 – 5 mm wide, flat; prairies
C. tetanica
 
105 Perigynia inflated and shiny; pistillate spikes sessile, globular
106
105 Perigynia not both inflated and shiny; pistillate spikes nearly sessile to stalked, elongate
107
 
106 Perigynia ~ 7 mm long; style not withering at maturity; plant 50 – 80 cm tall
C. oligosperma
106 Perigynia 2 – 4 mm long; style withering at maturity; plant 5 – 20 cm tall
C. supina var. spaniocarpa
 
107 Perigynia conspicuously many nerved
108
107 Perigynia obscurely nerved, may have 2 conspicuous marginal nerves
113
 
108 Perigynia spreading to reflexed
C. cryptolepis
108 Perigynia ascending to appressed
109
 
109 Culms lateral, previous year’s leaves on separate shoots
C. buxbaumii
109 Culms central, surrounded by persistent leaves of preceding year’s growth
110
 
110 Stem leaves absent or only a few towards base of stem; perigynia 1.5 – 2.5 mm long; pistillate scales 1.5 – 2.5 mm long
111
110 Stems leaves on lower 1/4 of stem; perigynia 3 – 4.5 mm long; pistillate scales > 2.5 mm long
112
 
111 Scales as long as perigynia, brownish; stems obtusely triangular
C. parryana var. parryana
111 Scales much shorter than perigynia, purplish; stem sharply triangular
C. norvegica ssp. inferalpina
 
112 Perigynia almost circular, little puncticulate; terminal spike staminate; Cypress Hills
C. raynoldsii
112 Perigynia flattened, markedly puncticulate; terminal spike gynaecandrous; northern mixed wood forest
C. raymondii
 
113 Perigynia subterete; achenes smooth surfaced
C. glacialis
113 Perigynia flat-triangular to lenticular; achenes papillate
114
 
114 Rootlets with yellow fuzz; terminal spike staminate
115
114 Rootlets without yellow fuzz; terminal spike gynaecandrous
116
 
115 Pistillate scales long acuminate; staminate spike 4 – 12 mm; leaves to 3 mm broad, flat
C. magellanica ssp. irrigua
115 Pistillate scale acute; staminate spike 10 – 30 mm; leaves less than or equal to 3 mm broad, somewhat involute
C. limosa
 
116 Culms lateral, previous year’s leaves on separate shoots
C. buxbaumii
116 Culms central, surrounded by persistent leaves from preceding years
C. norvegica ssp. inferalpina