OregonFlora: Carex geyeri vs. Carex pachycarpa

	Carex geyeri	Carex pachycarpa
	elk sedge	many-rib sedge
Habit	Plants loosely cespitose or short rhizomatous, with thick, dark, shallow rhizomes; culms 12–50 cm, triangular in cross section.	Plants cespitose, 14–110 cm tall.
Leaves	1.1–3.5 mm wide; flat; evergreen; leathery; as long as or longer than the culms.	(2)3–5 mm wide.
Inflorescences	spike solitary, androgynous, lacking inflorescence bracts; male terminal portion 1–2.5 cm long, separated from the 1–3 perigynia by a short internode.	1.6–3 cm × 12–20 mm; dense and head-like; spikes gynaecandrous, occasionally female.
Perigynia	obovate, rounded at the top, 5–7(8.5) × 1.8–2.8 mm, green; whitish, or brown; beak small; stigmas 3.	smoothly oval to obovate; plano-convex; (3.8)4.4–5.8(6.5) × (1.4)1.8–2.8(3.3) mm, cream-colored or tan with green “shoulders,” becoming uniformly straw-colored with age; dorsal veins (8)10–17 and on dried specimens usually appearing sunken; ventral veins (0)4–12; wing (0.2)0.3–0.4(0.5) mm wide; broad near the beak but narrow lower on the body; beak winged nearly to the tip, 2–2.8(3.3) mm from achene top to beak tip; stigmas 2.
Achenes	trigonous.	lenticular, 1.7–2.4 × 1.1–1.7 mm.
Female scales	the lower longer than the perigynia; the upper reduced; more or less brown with paler midrib and margins, pointed to awned.	(3.2)3.9–4.8 mm; gold or light brown with paler midrib and margins; longer and narrower than the perigynia.

	Carex geyeri	Carex pachycarpa
Distribution	[WildflowerSearch map] [BONAP county map]	[WildflowerSearch map]
Discussion	Well-drained soils in dry, open, conifer forests, aspen stands, and openings, rarely in sagebrush, on both serpentine and nonserpentine substrates. 100–2500 m. BR, BW, Col, ECas, Lava, Owy, Sisk. CA, ID, NV, WA; north to southeastern British Columbia, east to CO, PA. Native. Carex geyeri is a common ground cover in open forest, especially in northeastern Oregon, recognized by its tough, flat, evergreen leaves from dark, scaly rhizomes. Similar pinegrass, Calamagrostis rubescens, usually has hairy internodes and when in flower it is easily distinguished. Carex geyeri is important food for wildlife and livestock, especially in winter. In southwestern Oregon, C. geyeri can be confused with C. multicaulis, which is densely cespitose and has proportionately shorter, usually involute leaves, and longer, green, leaf-like, lower female scales.	Dry grasslands, mesic meadows and open forests. 600–2800 m. BR, BW, Casc, ECas, Sisk. CA, ID, NV, WA; northeast to MT. Native. Carex pachycarpa is a “ball-headed” bunchgrass sedge with large, pale, shaggy heads. Its pale perigynia have smooth oval bodies and wings that are broad near the beak but taper smoothly to become narrow beside the achene. Dorsal perigynium veins may appear impressed rather than raised. Individuals in the Warner Mountains may have unusually long, lanceolate perigynia. Other montane upland species (within subkey 9) with dense heads have darker or more compact inflorescences. This species can be confused with Californian C. multicostata.
Source	Flora of Oregon, volume 1, page 202 Barbara Wilson, Richard Brainerd, Nick Otting	Flora of Oregon, volume 1, page 218 Barbara Wilson, Richard Brainerd, Nick Otting
Sibling taxa	C. abrupta, C. agastachys, C. amplifolia, C. angustata, C. aperta, C. aquatilis, C. arcta, C. arenaria, C. atherodes, C. athrostachya, C. atrosquama, C. aurea, C. barbarae, C. bebbii, C. bolanderi, C. brainerdii, C. brevior, C. breweri, C. buchananii, C. buxbaumii, C. californica, C. canescens, C. capillaris, C. capitata, C. chordorrhiza, C. comans, C. comosa, C. concinna, C. concinnoides, C. cordillerana, C. crawfordii, C. cusickii, C. davyi, C. deflexa, C. densa, C. diandra, C. disperma, C. distans, C. douglasii, C. duriuscula, C. echinata, C. exsiccata, C. feta, C. filifolia, C. fissuricola, C. fracta, C. gynocrates, C. gynodynama, C. halliana, C. harfordii, C. hassei, C. haydeniana, C. hendersonii, C. heteroneura, C. hirsutella, C. hirta, C. hoodii, C. hystericina, C. idahoa, C. illota, C. infirminervia, C. inops, C. integra, C. interior, C. interrupta, C. jonesii, C. kelloggii, C. klamathensis, C. kobomugi, C. laeviculmis, C. lasiocarpa, C. leporina, C. leporinella, C. leptalea, C. leptopoda, C. limosa, C. livida, C. longii, C. luzulina, C. lyngbyei, C. macrocephala, C. macrochaeta, C. media, C. mendocinensis, C. mertensii, C. mesochorea, C. micropoda, C. microptera, C. multicaulis, C. nardina, C. nebrascensis, C. nervina, C. neurophora, C. nigricans, C. nudata, C. obnupta, C. pachycarpa, C. pachystachya, C. pansa, C. paysonis, C. pellita, C. pelocarpa, C. pendula, C. petasata, C. phaeocephala, C. pluriflora, C. praeceptorum, C. praegracilis, C. praticola, C. preslii, C. pumila, C. raynoldsii, C. retrorsa, C. rossii, C. saxatilis, C. scabriuscula, C. scirpoidea, C. scoparia, C. scopulorum, C. serpenticola, C. serratodens, C. sheldonii, C. simulata, C. spectabilis, C. stipata, C. straminiformis, C. subbracteata, C. subfusca, C. subnigricans, C. sychnocephala, C. tahoensis, C. tiogana, C. tribuloides, C. tumulicola, C. unilateralis, C. utriculata, C. vallicola, C. vernacula, C. vesicaria, C. viridula, C. vulpinoidea, C. whitneyi, C. zikae	C. abrupta, C. agastachys, C. amplifolia, C. angustata, C. aperta, C. aquatilis, C. arcta, C. arenaria, C. atherodes, C. athrostachya, C. atrosquama, C. aurea, C. barbarae, C. bebbii, C. bolanderi, C. brainerdii, C. brevior, C. breweri, C. buchananii, C. buxbaumii, C. californica, C. canescens, C. capillaris, C. capitata, C. chordorrhiza, C. comans, C. comosa, C. concinna, C. concinnoides, C. cordillerana, C. crawfordii, C. cusickii, C. davyi, C. deflexa, C. densa, C. diandra, C. disperma, C. distans, C. douglasii, C. duriuscula, C. echinata, C. exsiccata, C. feta, C. filifolia, C. fissuricola, C. fracta, C. geyeri, C. gynocrates, C. gynodynama, C. halliana, C. harfordii, C. hassei, C. haydeniana, C. hendersonii, C. heteroneura, C. hirsutella, C. hirta, C. hoodii, C. hystericina, C. idahoa, C. illota, C. infirminervia, C. inops, C. integra, C. interior, C. interrupta, C. jonesii, C. kelloggii, C. klamathensis, C. kobomugi, C. laeviculmis, C. lasiocarpa, C. leporina, C. leporinella, C. leptalea, C. leptopoda, C. limosa, C. livida, C. longii, C. luzulina, C. lyngbyei, C. macrocephala, C. macrochaeta, C. media, C. mendocinensis, C. mertensii, C. mesochorea, C. micropoda, C. microptera, C. multicaulis, C. nardina, C. nebrascensis, C. nervina, C. neurophora, C. nigricans, C. nudata, C. obnupta, C. pachystachya, C. pansa, C. paysonis, C. pellita, C. pelocarpa, C. pendula, C. petasata, C. phaeocephala, C. pluriflora, C. praeceptorum, C. praegracilis, C. praticola, C. preslii, C. pumila, C. raynoldsii, C. retrorsa, C. rossii, C. saxatilis, C. scabriuscula, C. scirpoidea, C. scoparia, C. scopulorum, C. serpenticola, C. serratodens, C. sheldonii, C. simulata, C. spectabilis, C. stipata, C. straminiformis, C. subbracteata, C. subfusca, C. subnigricans, C. sychnocephala, C. tahoensis, C. tiogana, C. tribuloides, C. tumulicola, C. unilateralis, C. utriculata, C. vallicola, C. vernacula, C. vesicaria, C. viridula, C. vulpinoidea, C. whitneyi, C. zikae
Synonyms		Carex multicostata
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Carex pachycarpa

elk sedge

many-rib sedge

Habit

Plants loosely cespitose or short rhizomatous, with thick, dark, shallow rhizomes; culms 12–50 cm, triangular in cross section.

Plants cespitose, 14–110 cm tall.

Leaves

1.1–3.5 mm wide; flat; evergreen; leathery; as long as or longer than the culms.

(2)3–5 mm wide.

Inflorescences

spike solitary, androgynous, lacking inflorescence bracts; male terminal portion 1–2.5 cm long, separated from the 1–3 perigynia by a short internode.

1.6–3 cm × 12–20 mm; dense and head-like;

spikes gynaecandrous, occasionally female.

Perigynia

obovate, rounded at the top, 5–7(8.5) × 1.8–2.8 mm, green; whitish, or brown;

beak small;

stigmas 3.

smoothly oval to obovate; plano-convex; (3.8)4.4–5.8(6.5) × (1.4)1.8–2.8(3.3) mm, cream-colored or tan with green “shoulders,” becoming uniformly straw-colored with age; dorsal veins (8)10–17 and on dried specimens usually appearing sunken; ventral veins (0)4–12;

wing (0.2)0.3–0.4(0.5) mm wide; broad near the beak but narrow lower on the body;

beak winged nearly to the tip, 2–2.8(3.3) mm from achene top to beak tip;

stigmas 2.

Achenes

trigonous.

lenticular, 1.7–2.4 × 1.1–1.7 mm.

Female scales

the lower longer than the perigynia; the upper reduced; more or less brown with paler midrib and margins, pointed to awned.

(3.2)3.9–4.8 mm; gold or light brown with paler midrib and margins; longer and narrower than the perigynia.

Carex geyeri

Carex pachycarpa

Distribution

[WildflowerSearch map]

[BONAP county map]

[WildflowerSearch map]

Discussion

Well-drained soils in dry, open, conifer forests, aspen stands, and openings, rarely in sagebrush, on both serpentine and nonserpentine substrates. 100–2500 m. BR, BW, Col, ECas, Lava, Owy, Sisk. CA, ID, NV, WA; north to southeastern British Columbia, east to CO, PA. Native.

Carex geyeri is a common ground cover in open forest, especially in northeastern Oregon, recognized by its tough, flat, evergreen leaves from dark, scaly rhizomes. Similar pinegrass, Calamagrostis rubescens, usually has hairy internodes and when in flower it is easily distinguished. Carex geyeri is important food for wildlife and livestock, especially in winter. In southwestern Oregon, C. geyeri can be confused with C. multicaulis, which is densely cespitose and has proportionately shorter, usually involute leaves, and longer, green, leaf-like, lower female scales.

Dry grasslands, mesic meadows and open forests. 600–2800 m. BR, BW, Casc, ECas, Sisk. CA, ID, NV, WA; northeast to MT. Native.

Carex pachycarpa is a “ball-headed” bunchgrass sedge with large, pale, shaggy heads. Its pale perigynia have smooth oval bodies and wings that are broad near the beak but taper smoothly to become narrow beside the achene. Dorsal perigynium veins may appear impressed rather than raised. Individuals in the Warner Mountains may have unusually long, lanceolate perigynia. Other montane upland species (within subkey 9) with dense heads have darker or more compact inflorescences. This species can be confused with Californian C. multicostata.

Source

Flora of Oregon, volume 1, page 202
Barbara Wilson, Richard Brainerd, Nick Otting

Flora of Oregon, volume 1, page 218
Barbara Wilson, Richard Brainerd, Nick Otting

Sibling taxa