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thinfruit sedge

weak sedge, white-edge sedge

Habit Plants densely cespitose; rhizome internodes 1.2–2.8 mm thick. Plants densely cespitose.
Culms

yellow-brown at base, 10–60(–75) cm.

dark maroon at base; flowering stems 25–100 cm, as long as leaves at maturity or often longer, 0.5–1 mm thick, glabrous but scabrous within inflorescence.

Leaves

sheaths glabrous;

blades glaucous, widest blades 6.3–14.7 mm wide, smooth abaxially or sparsely antrorsely scaberulous on main veins.

basal sheaths maroon, bladeless, glabrous or rarely minutely pubescent;

others grading from maroon to green on back, pale brown-hyaline or reddish brown on front, often red dotted, sometimes finely pubescent;

blades flat, 2–7 mm wide, glabrous on both surfaces, margins and abaxial midribs often finely scabrous.

Inflorescences

0.40–1 of culm height;

peduncles of lateral spikes smooth;

peduncles of terminal spikes 0.7–20(–51) mm, barely to much exceeding lateral spikes;

proximal bract sheath loose, abaxially glabrous, sheath front apex truncate;

ligules (3–)4.7–9 mm;

distal bract slightly shorter than to much exceeding terminal spike.

peduncles of lateral spikes slender, to 50 mm, usually shorter than spikes or only slightly longer, scabrous; of terminal spike 15–50 mm, finely scabrous;

proximal bracts longer, or more often, shorter than inflorescences;

sheaths 1–7 cm;

blades 1–3.5 mm wide.

Spikes

4–6, distal 2–4 overlapping;

lateral spikes pistillate, with 12–39 perigynia, 11–41 × (5–)5.7–8(–9.6) mm, ratio of spike length (in mm) to flower number = (0.86–)1–1.3(–1.6);

terminal spikes 6–34 × 1–3.2 mm.

Perigynia

spirally imbricate, 44–57-veined, unwrinkled, oblong-ovoid, (4–)4.2–5.5(–6) × (1.5–)1.7–2.4 mm, (2–)2.2–2.8(–3.1) times as long as wide, obtusely triangular in cross section, dull, base very gradually tapered, apex gradually tapered;

beak absent or straight, 0–0.3 mm.

green to olive-green, usually red dotted, prominently 2-ribbed, finely 12–20-veined, loosely enveloping achene, fusiform to lance-ovoid, 5–9.5 × 1.1–2.2 mm, membranous, base acute, apex tapering gradually to abruptly contracted beak, glabrous or short-pubescent;

beak bidentate 0.7–2 mm, including teeth to 1 mm.

Achenes

obovoid, 2.5–3.4 × (1.3–)1.4–1.6(–1.7) mm, 0.37–0.5 times as long as perigynia, loosely enveloped by perigynia;

stipe straight, (0.2–)0.3–0.5(–0.6) mm;

beak straight or bent less than 30°, (0.1–)0.2–0.4(–0.5) mm.

stipitate, 1.9–2.5 × 1–1.5 mm, stipe 0.5–1.5 mm.

Pistillate

scales 1.9–2.8(–3.1) × (1.5–)1.7–2.4 mm, margins whitish, entire, apex awnless or with awn to 0.6(–1.6) mm.

scales white-hyaline, sometimes tinged with pale brown or suffused with chestnut, with broad green midrib, finely red dotted, oblong, 2.8–6 mm, much shorter than mature perigynia, apex obtuse, acute or cuspidate, awn to 0.2 mm, glabrous, distal margin ciliate.

Staminate

scales 3.8–5.3  1–1.8 mm.

Anthers

1.6–2 mm.

Lateral

spikes 2–5, 1 per node, well separated, erect at anthesis, soon nodding, pistillate with 10–25 perigynia attached 2–9 mm apart, linear, 25–80 × 2–3 mm.

Terminal

spike staminate or sometimes gynecandrous with a few pistillate flowers distally; 15–50 × 0.6–1.2 mm.

Carex flaccosperma

Carex debilis

Phenology Fruiting spring.
Habitat Wet-mesic deciduous forests, usually in acidic loams low in calcium, on flood plains and in swamps
Elevation 0–200 m (0–700 ft)
Distribution
from FNA
AL; AR; FL; GA; KS; KY; LA; MO; MS; NC; OK; SC; TN; TX; VA
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; CT; DC; DE; FL; GA; IL; IN; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NH; NJ; NY; OH; OK; PA; RI; SC; TN; TX; VA; VT; WI; WV; NB; NS; ON; PE; QC
[WildflowerSearch map]
[BONAP county map]
Discussion

Carex flaccosperma is frequent, especially on the Coastal Plain west of Alabama. It grows frequently with C. caroliniana, C. corrugata, and C. crus-corvi and occurs occasionally with C. glaucodea. When C. flaccosperma and C. glaucodea co-occur, C. flaccosperma usually inhabits slightly wetter soils than C. glaucodea. Natural hybrids between C. flaccosperma and C. glaucodea form rarely and are sterile (R. F. C. Naczi 1991). Hybrids have been collected in Arkansas, Louisiana, Missouri, and Oklahoma.

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

Varieties 2 (2 in the flora).

Carex debilis is extremely variable and has been variously subdivided into as many as six varieties or three subspecies. Only two weakly differentiated varieties can be maintained: the typical variety with broadly southern distribution and C. debilis var. rudgei, which replaces it in the Northeast, the Midwest, and the eastern mountains. Both varieties appear to hybridize with C. virescens but these hybrids have not been studied to confirm parentage.

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

Key
1. Perigynia fusiform, 5.5–9.5 mm, tapering very gradually to elongate beak; pistillate scales usually with apex blunt to acute, rarely cuspidate, white or very pale hyaline margins.
var. debilis
1. Perigynia lance-ellipsoid, 5–6.2 mm, more abruptly narrowed to beak; pistillate scales with apex acute to cuspidate to short-awned, hyaline margins usually suffused or streaked with reddish brown.
var. rudgei
Source FNA vol. 23, p. 457. FNA vol. 23, p. 469.
Parent taxa Cyperaceae > Carex > sect. Griseae Cyperaceae > Carex > sect. Hymenochlaenae
Sibling taxa
C. aboriginum, C. abrupta, C. abscondita, C. acidicola, C. acutiformis, C. adelostoma, C. adusta, C. aestivalis, C. aggregata, C. alata, C. albicans, C. albida, C. albolutescens, C. albonigra, C. albursina, C. alma, C. alopecoidea, C. amphibola, C. amplectens, C. amplifolia, C. angustata, C. annectens, C. anthoxanthea, C. aperta, C. appalachica, C. aquatilis, C. arapahoensis, C. arcta, C. arctata, C. arctiformis, C. arenaria, C. argyrantha, C. arkansana, C. assiniboinensis, C. atherodes, C. athrostachya, C. atlantica, C. atrata, C. atratiformis, C. atrofusca, C. atrosquama, C. aurea, C. aureolensis, C. austrina, C. austrocaroliniana, C. backii, C. baileyi, C. baltzellii, C. barbarae, C. barrattii, C. basiantha, C. bebbii, C. bella, C. bicknellii, C. bicolor, C. bigelowii, C. biltmoreana, C. blanda, C. bolanderi, C. bonanzensis, C. brainerdii, C. brevicaulis, C. brevior, C. breweri, C. bromoides, C. brunnescens, C. brysonii, C. bulbostylis, C. bullata, C. bushii, C. buxbaumii, C. calcifugens, C. californica, C. canescens, C. capillaris, C. capitata, C. careyana, C. caroliniana, C. caryophyllea, C. castanea, C. cephaloidea, C. cephalophora, C. chalciolepis, C. chapmanii, C. cherokeensis, C. chihuahuensis, C. chordorrhiza, C. circinata, C. collinsii, C. communis, C. comosa, C. complanata, C. concinna, C. concinnoides, C. congdonii, C. conjuncta, C. conoidea, C. constanceana, C. cordillerana, C. corrugata, C. crawei, C. crawfordii, C. crebriflora, C. crinita, C. cristatella, C. crus-corvi, C. cryptolepis, C. cumberlandensis, C. cumulata, C. curatorum, C. cusickii, C. dasycarpa, C. davisii, C. davyi, C. debilis, C. decomposita, C. deflexa, C. densa, C. deweyana, C. diandra, C. digitalis, C. diluta, C. disperma, C. distans, C. disticha, C. divisa, C. divulsa, C. douglasii, C. duriuscula, C. ebenea, C. eburnea, C. echinata, C. edwardsiana, C. egglestonii, C. eleusinoides, C. elliottii, C. elynoides, C. emoryi, C. endlichii, C. engelmannii, C. epapillosa, C. exilis, C. exsiccata, C. extensa, C. festucacea, C. feta, C. filifolia, C. fissa, C. fissuricola, C. flacca, C. flava, C. floridana, C. foenea, C. folliculata, C. formosa, C. fracta, C. frankii, C. fuliginosa, C. garberi, C. geophila, C. geyeri, C. gholsonii, C. gigantea, C. glacialis, C. glareosa, C. glaucescens, C. glaucodea, C. globosa, C. gmelinii, C. godfreyi, C. gracilescens, C. gracilior, C. gracillima, C. granularis, C. gravida, C. grayi, C. grisea, C. gynandra, C. gynocrates, C. gynodynama, C. halliana, C. hallii, C. harfordii, C. hassei, C. haydeniana, C. haydenii, C. heleonastes, C. helleri, C. hendersonii, C. heteroneura, C. heterostachya, C. hirsutella, C. hirta, C. hirtifolia, C. hirtissima, C. hitchcockiana, C. holostoma, C. hoodii, C. hookeriana, C. hormathodes, C. hostiana, C. houghtoniana, C. hyalina, C. hyalinolepis, C. hystericina, C. idahoa, C. illota, C. impressinervia, C. incurviformis, C. infirminervia, C. inops, C. integra, C. interior, C. interrupta, C. intumescens, C. jamesii, C. jonesii, C. joorii, C. juniperorum, C. kobomugi, C. kraliana, C. krausei, C. lachenalii, C. lacustris, C. laeviconica, C. laeviculmis, C. laevivaginata, C. lapponica, C. lasiocarpa, C. latebracteata, C. lativena, C. laxa, C. laxiculmis, C. laxiflora, C. leavenworthii, C. lemmonii, C. lenticularis, C. leporinella, C. leptalea, C. leptonervia, C. leptopoda, C. limosa, C. livida, C. loliacea, C. lonchocarpa, C. longii, C. louisianica, C. lucorum, C. lupuliformis, C. lupulina, C. lurida, C. lutea, C. luzulifolia, C. luzulina, C. lyngbyei, C. mackenziei, C. macloviana, C. macrocephala, C. macrochaeta, C. magellanica, C. manhartii, C. marina, C. mariposana, C. maritima, C. mckittrickensis, C. meadii, C. media, C. melanostachya, C. membranacea, C. mendocinensis, C. merritt-fernaldii, C. mertensii, C. mesochorea, C. michauxiana, C. microchaeta, C. microdonta, C. microglochin, C. micropoda, C. microptera, C. misera, C. missouriensis, C. mitchelliana, C. molesta, C. molestiformis, C. muehlenbergii, C. multicaulis, C. multicostata, C. muricata, C. muriculata, C. muskingumensis, C. nardina, C. nebrascensis, C. nelsonii, C. nervina, C. neurophora, C. nigra, C. nigricans, C. nigromarginata, C. normalis, C. norvegica, C. nova, C. novae-angliae, C. nudata, C. obispoensis, C. obnupta, C. obtusata, C. occidentalis, C. oklahomensis, C. oligocarpa, C. oligosperma, C. opaca, C. oreocharis, C. ormostachya, C. oronensis, C. ouachitana, C. ovalis, C. oxylepis, C. ozarkana, C. pachystachya, C. paeninsulae, C. paleacea, C. pallescens, C. panicea, C. pansa, C. parallela, C. parryana, C. pauciflora, C. paysonis, C. peckii, C. pedunculata, C. pellita, C. pelocarpa, C. pendula, C. pensylvanica, C. perdentata, C. perglobosa, C. petasata, C. petricosa, C. phaeocephala, C. picta, C. pigra, C. pityophila, C. planispicata, C. planostachys, C. plantaginea, C. platyphylla, C. pluriflora, C. podocarpa, C. polymorpha, C. praeceptorum, C. praegracilis, C. prairea, C. prasina, C. praticola, C. preslii, C. projecta, C. proposita, C. pseudocyperus, C. pumila, C. purpurifera, C. radfordii, C. radiata, C. ramenskii, C. rariflora, C. raynoldsii, C. recta, C. reniformis, C. retroflexa, C. retrorsa, C. richardsonii, C. roanensis, C. rosea, C. rossii, C. rostrata, C. rotundata, C. rufina, C. rupestris, C. ruthii, C. sabulosa, C. salina, C. sartwelliana, C. sartwellii, C. saxatilis, C. saximontana, C. scabrata, C. scabriuscula, C. schottii, C. schweinitzii, C. scirpoidea, C. scoparia, C. scopulorum, C. senta, C. seorsa, C. serpenticola, C. serratodens, C. sheldonii, C. shinnersii, C. shortiana, C. siccata, C. silicea, C. simulata, C. socialis, C. sparganioides, C. specifica, C. spectabilis, C. specuicola, C. spicata, C. spissa, C. sprengelii, C. squarrosa, C. stenoptila, C. sterilis, C. stevenii, C. stipata, C. straminea, C. straminiformis, C. striata, C. striatula, C. stricta, C. styloflexa, C. stylosa, C. subbracteata, C. suberecta, C. subfusca, C. subnigricans, C. subspathacea, C. superata, C. supina, C. swanii, C. sychnocephala, C. sylvatica, C. tahoensis, C. tenax, C. tenera, C. tenuiflora, C. tetanica, C. tetrastachya, C. texensis, C. thornei, C. thurberi, C. timida, C. tincta, C. tompkinsii, C. tonsa, C. torreyi, C. torta, C. triangularis, C. tribuloides, C. trichocarpa, C. triquetra, C. trisperma, C. tuckermanii, C. tumulicola, C. turbinata, C. turgescens, C. typhina, C. umbellata, C. unilateralis, C. ursina, C. utriculata, C. vacillans, C. vaginata, C. vallicola, C. venusta, C. vernacula, C. verrucosa, C. vesicaria, C. vestita, C. vexans, C. virescens, C. viridula, C. vulpinoidea, C. whitneyi, C. wiegandii, C. willdenowii, C. williamsii, C. woodii, C. wootonii, C. xerantica
C. aboriginum, C. abrupta, C. abscondita, C. acidicola, C. acutiformis, C. adelostoma, C. adusta, C. aestivalis, C. aggregata, C. alata, C. albicans, C. albida, C. albolutescens, C. albonigra, C. albursina, C. alma, C. alopecoidea, C. amphibola, C. amplectens, C. amplifolia, C. angustata, C. annectens, C. anthoxanthea, C. aperta, C. appalachica, C. aquatilis, C. arapahoensis, C. arcta, C. arctata, C. arctiformis, C. arenaria, C. argyrantha, C. arkansana, C. assiniboinensis, C. atherodes, C. athrostachya, C. atlantica, C. atrata, C. atratiformis, C. atrofusca, C. atrosquama, C. aurea, C. aureolensis, C. austrina, C. austrocaroliniana, C. backii, C. baileyi, C. baltzellii, C. barbarae, C. barrattii, C. basiantha, C. bebbii, C. bella, C. bicknellii, C. bicolor, C. bigelowii, C. biltmoreana, C. blanda, C. bolanderi, C. bonanzensis, C. brainerdii, C. brevicaulis, C. brevior, C. breweri, C. bromoides, C. brunnescens, C. brysonii, C. bulbostylis, C. bullata, C. bushii, C. buxbaumii, C. calcifugens, C. californica, C. canescens, C. capillaris, C. capitata, C. careyana, C. caroliniana, C. caryophyllea, C. castanea, C. cephaloidea, C. cephalophora, C. chalciolepis, C. chapmanii, C. cherokeensis, C. chihuahuensis, C. chordorrhiza, C. circinata, C. collinsii, C. communis, C. comosa, C. complanata, C. concinna, C. concinnoides, C. congdonii, C. conjuncta, C. conoidea, C. constanceana, C. cordillerana, C. corrugata, C. crawei, C. crawfordii, C. crebriflora, C. crinita, C. cristatella, C. crus-corvi, C. cryptolepis, C. cumberlandensis, C. cumulata, C. curatorum, C. cusickii, C. dasycarpa, C. davisii, C. davyi, C. decomposita, C. deflexa, C. densa, C. deweyana, C. diandra, C. digitalis, C. diluta, C. disperma, C. distans, C. disticha, C. divisa, C. divulsa, C. douglasii, C. duriuscula, C. ebenea, C. eburnea, C. echinata, C. edwardsiana, C. egglestonii, C. eleusinoides, C. elliottii, C. elynoides, C. emoryi, C. endlichii, C. engelmannii, C. epapillosa, C. exilis, C. exsiccata, C. extensa, C. festucacea, C. feta, C. filifolia, C. fissa, C. fissuricola, C. flacca, C. flaccosperma, C. flava, C. floridana, C. foenea, C. folliculata, C. formosa, C. fracta, C. frankii, C. fuliginosa, C. garberi, C. geophila, C. geyeri, C. gholsonii, C. gigantea, C. glacialis, C. glareosa, C. glaucescens, C. glaucodea, C. globosa, C. gmelinii, C. godfreyi, C. gracilescens, C. gracilior, C. gracillima, C. granularis, C. gravida, C. grayi, C. grisea, C. gynandra, C. gynocrates, C. gynodynama, C. halliana, C. hallii, C. harfordii, C. hassei, C. haydeniana, C. haydenii, C. heleonastes, C. helleri, C. hendersonii, C. heteroneura, C. heterostachya, C. hirsutella, C. hirta, C. hirtifolia, C. hirtissima, C. hitchcockiana, C. holostoma, C. hoodii, C. hookeriana, C. hormathodes, C. hostiana, C. houghtoniana, C. hyalina, C. hyalinolepis, C. hystericina, C. idahoa, C. illota, C. impressinervia, C. incurviformis, C. infirminervia, C. inops, C. integra, C. interior, C. interrupta, C. intumescens, C. jamesii, C. jonesii, C. joorii, C. juniperorum, C. kobomugi, C. kraliana, C. krausei, C. lachenalii, C. lacustris, C. laeviconica, C. laeviculmis, C. laevivaginata, C. lapponica, C. lasiocarpa, C. latebracteata, C. lativena, C. laxa, C. laxiculmis, C. laxiflora, C. leavenworthii, C. lemmonii, C. lenticularis, C. leporinella, C. leptalea, C. leptonervia, C. leptopoda, C. limosa, C. livida, C. loliacea, C. lonchocarpa, C. longii, C. louisianica, C. lucorum, C. lupuliformis, C. lupulina, C. lurida, C. lutea, C. luzulifolia, C. luzulina, C. lyngbyei, C. mackenziei, C. macloviana, C. macrocephala, C. macrochaeta, C. magellanica, C. manhartii, C. marina, C. mariposana, C. maritima, C. mckittrickensis, C. meadii, C. media, C. melanostachya, C. membranacea, C. mendocinensis, C. merritt-fernaldii, C. mertensii, C. mesochorea, C. michauxiana, C. microchaeta, C. microdonta, C. microglochin, C. micropoda, C. microptera, C. misera, C. missouriensis, C. mitchelliana, C. molesta, C. molestiformis, C. muehlenbergii, C. multicaulis, C. multicostata, C. muricata, C. muriculata, C. muskingumensis, C. nardina, C. nebrascensis, C. nelsonii, C. nervina, C. neurophora, C. nigra, C. nigricans, C. nigromarginata, C. normalis, C. norvegica, C. nova, C. novae-angliae, C. nudata, C. obispoensis, C. obnupta, C. obtusata, C. occidentalis, C. oklahomensis, C. oligocarpa, C. oligosperma, C. opaca, C. oreocharis, C. ormostachya, C. oronensis, C. ouachitana, C. ovalis, C. oxylepis, C. ozarkana, C. pachystachya, C. paeninsulae, C. paleacea, C. pallescens, C. panicea, C. pansa, C. parallela, C. parryana, C. pauciflora, C. paysonis, C. peckii, C. pedunculata, C. pellita, C. pelocarpa, C. pendula, C. pensylvanica, C. perdentata, C. perglobosa, C. petasata, C. petricosa, C. phaeocephala, C. picta, C. pigra, C. pityophila, C. planispicata, C. planostachys, C. plantaginea, C. platyphylla, C. pluriflora, C. podocarpa, C. polymorpha, C. praeceptorum, C. praegracilis, C. prairea, C. prasina, C. praticola, C. preslii, C. projecta, C. proposita, C. pseudocyperus, C. pumila, C. purpurifera, C. radfordii, C. radiata, C. ramenskii, C. rariflora, C. raynoldsii, C. recta, C. reniformis, C. retroflexa, C. retrorsa, C. richardsonii, C. roanensis, C. rosea, C. rossii, C. rostrata, C. rotundata, C. rufina, C. rupestris, C. ruthii, C. sabulosa, C. salina, C. sartwelliana, C. sartwellii, C. saxatilis, C. saximontana, C. scabrata, C. scabriuscula, C. schottii, C. schweinitzii, C. scirpoidea, C. scoparia, C. scopulorum, C. senta, C. seorsa, C. serpenticola, C. serratodens, C. sheldonii, C. shinnersii, C. shortiana, C. siccata, C. silicea, C. simulata, C. socialis, C. sparganioides, C. specifica, C. spectabilis, C. specuicola, C. spicata, C. spissa, C. sprengelii, C. squarrosa, C. stenoptila, C. sterilis, C. stevenii, C. stipata, C. straminea, C. straminiformis, C. striata, C. striatula, C. stricta, C. styloflexa, C. stylosa, C. subbracteata, C. suberecta, C. subfusca, C. subnigricans, C. subspathacea, C. superata, C. supina, C. swanii, C. sychnocephala, C. sylvatica, C. tahoensis, C. tenax, C. tenera, C. tenuiflora, C. tetanica, C. tetrastachya, C. texensis, C. thornei, C. thurberi, C. timida, C. tincta, C. tompkinsii, C. tonsa, C. torreyi, C. torta, C. triangularis, C. tribuloides, C. trichocarpa, C. triquetra, C. trisperma, C. tuckermanii, C. tumulicola, C. turbinata, C. turgescens, C. typhina, C. umbellata, C. unilateralis, C. ursina, C. utriculata, C. vacillans, C. vaginata, C. vallicola, C. venusta, C. vernacula, C. verrucosa, C. vesicaria, C. vestita, C. vexans, C. virescens, C. viridula, C. vulpinoidea, C. whitneyi, C. wiegandii, C. willdenowii, C. williamsii, C. woodii, C. wootonii, C. xerantica
Subordinate taxa
C. debilis var. debilis, C. debilis var. rudgei
Name authority Dewey: Amer. J. Sci. Arts, ser. 2, 2: 245. (1846) Michaux: Fl. Bor.-Amer. 2: 172. (1803)
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