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arctic rush

ringseed rush

Habit Herbs, perennial, 2–10 dm. Herbs, perennial, tufted, 1.5–3.5 dm.
Rhizomes

long- creeping.

poorly developed.

Culms

erect, 1–3 mm diam.

erect, compressed, bases often swollen.

Cataphylls

several.

Leaves

blade usually absent (present in var. mexicanus).

basal 2–4, cauline 1–3;

auricles 0.5–1 mm, apex rounded to nearly acute;

blade flat, 3–15 cm × 1–2.5 mm.

Inflorescences

lateral, 3–many-flowered, loose to congested;

primary bract barely exceeding to many times longer than inflorescence.

glomerules, (1–)2–5(–10), each with (3–)6–15 flowers, open;

primary bract shorter than inflorescence.

Flowers

variously pedicellate;

bracteoles membranous;

tepals chestnut brown or paler, lanceolate, (2.5–)3.3–5.5(–6) mm, margins clear;

inner series loosely subtending capsule at maturity; usually slightly shorter, margins scarious to clear, apex acutish to obtuse;

stamens 6, filaments 0.2–1.1 mm, anthers 0.9–2.2 mm;

style 0.9–1.5 mm.

tepals straw-colored with green midstripe, lanceolate or widely so, 3.5–5 mm, margins sometimes clear;

outer and inner series nearly equal;

stamens 3, filaments 1.5 mm, anthers 0.5 mm;

style 0.5 mm.

Capsules

3-locular or infrequently pseudo-3-locular, oblate to narrowly ovoid, 3.5–4(–4.5) mm, equal to or exceeding perianth.

tan to reddish brown, 3-locular, obovoid, 2.6–3.2 mm, shorter than perianth.

Seeds

dark amber, oblate to ellipsoid, 0.6–0.8 mm.

fusiform, 0.5–0.6 mm, not tailed.

Juncus arcticus

Juncus filipendulus

Phenology Flowering and fruiting spring–early summer.
Habitat Moist, usually calcareous soils of swales or glades, occasionally in shallow water along streams
Distribution
from FNA
AK; AR; AZ; CA; CO; DE; IA; ID; IL; IN; KS; MA; MD; ME; MI; MN; MO; MT; ND; NE; NH; NM; NV; NY; OH; OK; OR; PA; SD; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NS; NT; NU; ON; PE; QC; SK; YT; Mexico; South America; Asia
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; GA; KY; LA; MS; OK; TN; TX
[WildflowerSearch map]
[BONAP county map]
Discussion

Numerous entities have been circumscribed and recognized at various nomenclatural ranks by a plethora of authors addressing state or regional floras. In considering the Juncus arcticus-balticus complex as a whole in North America, one is soon confronted with a wide-ranging and obviously polymorphic complex that has not read the literature. It is abundantly clear that the systematics of the group will not be solved on the basis of morphology alone and that resolution of the problem is ripe for molecular investigations.

Varieties 3 7 (3 in the flora).

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

Key
1. Anthers about as long as filaments; blades absent
var. alaskanus
1. Anthers at least 2 times as long as filaments.
→ 2
2. Blade-bearing leaves absent
var. balticus
2. Distal 1 or 2 leaves with obvious blade
var. mexicanus
Source FNA vol. 22. FNA vol. 22.
Parent taxa Juncaceae > Juncus > subg. Genuini Juncaceae > Juncus > subg. Graminifolii
Sibling taxa
J. acuminatus, J. acutiflorus, J. acutus, J. alpinoarticulatus, J. anthelatus, J. articulatus, J. biglumis, J. bolanderi, J. brachycarpus, J. brachycephalus, J. brachyphyllus, J. brevicaudatus, J. bryoides, J. bufonius, J. bulbosus, J. caesariensis, J. canadensis, J. capillaris, J. capitatus, J. castaneus, J. chlorocephalus, J. compressus, J. confusus, J. cooperi, J. coriaceus, J. covillei, J. debilis, J. dichotomus, J. diffusissimus, J. drummondii, J. dubius, J. dudleyi, J. effusus, J. elliottii, J. ensifolius, J. falcatus, J. filiformis, J. filipendulus, J. georgianus, J. gerardii, J. greenei, J. gymnocarpus, J. hallii, J. hemiendytus, J. howellii, J. inflexus, J. interior, J. kelloggii, J. leiospermus, J. lesueurii, J. longistylis, J. luciensis, J. macrandrus, J. macrophyllus, J. marginatus, J. maritimus, J. megacephalus, J. mertensianus, J. militaris, J. nevadensis, J. nodatus, J. nodosus, J. occidentalis, J. orthophyllus, J. oxymeris, J. parryi, J. patens, J. pelocarpus, J. pervetus, J. phaeocephalus, J. polycephalus, J. regelii, J. repens, J. roemerianus, J. scirpoides, J. secundus, J. squarrosus, J. stygius, J. subcaudatus, J. subtilis, J. supiniformis, J. tenuis, J. texanus, J. textilis, J. tiehmii, J. torreyi, J. trifidus, J. triformis, J. triglumis, J. trigonocarpus, J. uncialis, J. validus, J. vaseyi, J. xiphioides
J. acuminatus, J. acutiflorus, J. acutus, J. alpinoarticulatus, J. anthelatus, J. arcticus, J. articulatus, J. biglumis, J. bolanderi, J. brachycarpus, J. brachycephalus, J. brachyphyllus, J. brevicaudatus, J. bryoides, J. bufonius, J. bulbosus, J. caesariensis, J. canadensis, J. capillaris, J. capitatus, J. castaneus, J. chlorocephalus, J. compressus, J. confusus, J. cooperi, J. coriaceus, J. covillei, J. debilis, J. dichotomus, J. diffusissimus, J. drummondii, J. dubius, J. dudleyi, J. effusus, J. elliottii, J. ensifolius, J. falcatus, J. filiformis, J. georgianus, J. gerardii, J. greenei, J. gymnocarpus, J. hallii, J. hemiendytus, J. howellii, J. inflexus, J. interior, J. kelloggii, J. leiospermus, J. lesueurii, J. longistylis, J. luciensis, J. macrandrus, J. macrophyllus, J. marginatus, J. maritimus, J. megacephalus, J. mertensianus, J. militaris, J. nevadensis, J. nodatus, J. nodosus, J. occidentalis, J. orthophyllus, J. oxymeris, J. parryi, J. patens, J. pelocarpus, J. pervetus, J. phaeocephalus, J. polycephalus, J. regelii, J. repens, J. roemerianus, J. scirpoides, J. secundus, J. squarrosus, J. stygius, J. subcaudatus, J. subtilis, J. supiniformis, J. tenuis, J. texanus, J. textilis, J. tiehmii, J. torreyi, J. trifidus, J. triformis, J. triglumis, J. trigonocarpus, J. uncialis, J. validus, J. vaseyi, J. xiphioides
Subordinate taxa
J. arcticus var. alaskanus, J. arcticus var. balticus, J. arcticus var. mexicanus
Synonyms J. leptocaulis
Name authority Willdenow: Sp. Pl. 2: 206. (1799) Buckley: Proceedings of the Academy of Natural Sciences of Philadelphia 14: 8. (1862)
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