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Hartweg's iris, rainbow iris, Sierra iris

iris de virginie, southern blue flag, Virginia iris

Rhizomes

creeping, not producing dense clumps, covered with remains of old leaves, slender to moderately thick, 0.5–0.9 cm diam.;

roots fibrous.

many-branched, forming dense clumps, 2–4 cm diam., usually covered with remnants of old leaves;

roots fleshy.

Stems

simple, solid, 0.5–3 dm.

rather weak, often falling over after flowering, solid, usually 1-branched, 5–10 dm.

Leaves

basal deciduous, blade pale green, not pink basally, 2–4.5 dm × 0.2–0.6(–1) cm, sometimes glaucous, margins not thickened;

cauline usually 1–several, spreading, sheathing for about 1/2 length, foliaceous, blade not inflated.

basal erect or often flexible, blade gray-green to bright green, buff to purplish basally, with several prominent ribs in mature leaves, linear-ensiform, 6–8 dm × 2.5–3 cm, apex acute.

Inflorescence units

1–2(–3)-flowered;

spathes divergent, separated by 1.5–4 cm, linear to linear-lanceolate, unequal, outer 5–11 cm × 4–7 mm, inner 5–6 cm × 2–3 mm, herbaceous, apex acute.

2–3-flowered, branch units 1–2-flowered;

spathes compact, often with brown striations, ridged, unequal, outer 3–8 cm, inner 8–14 cm, firm, herbaceous.

Flowers

perianth lavender, cream, or pale to deep yellow;

floral tube funnelform, 0.5–1(–1.5) cm;

sepals oblanceolate, 4–7 × 1.4–2 cm, base gradually attenuate;

petals narrowly oblanceolate, 3.5–6 × 0.5–1.1 cm, widest at about 1/2 their length, base abruptly attenuate, claw 1–2 mm wide;

ovary nearly cylindrical, 1–2 cm;

style 1.6–3 cm, crests overlapping, obtusely angled, 0.5–1.1 cm;

stigmas acutely triangular, margins entire;

pedicel 0.5–2.5 cm at anthesis, lengthening to 3.5–7.5 cm at maturity.

perianth lavender to violet, rarely white;

floral tube constricted above ovary, 1–2 cm;

sepals spreading and arched, pale blue to purple with darker blue or purple lines, obovate to oval, 4–8.4 × 1.6–4 cm, base abruptly attenuate, claw green in median, bordered by yellow ground with blue or purple lines, yellow extending onto base of limb as finely pubescent signal patch;

petals oblong-lanceolate to oblong-spatulate, 3–7 × 1–3 cm, claw greenish yellow with blue or purplish lines, apex often emarginate;

ovary trigonal, 1.3–3.8 cm;

style inwardly auriculate at convergences, 3–4.5 cm, crests reflexed, 0.7–2 cm;

stigmas unlobed, with prominent triangular tongues, margins entire;

pedicel 2.5–8 cm.

Capsules

oblong-oval, 3-angled, tapering abruptly at either end, 2–3 cm.

ovoid, ellipsoid, or long-cylindric, trigonal or polygonal in cross section, 3–6 × 1–2 cm.

Seeds

brown, irregularly D-shaped, wrinkled.

in 2 rows per locule, pale brown, usually D-shaped, 5–8 mm, pitted, corky.

2n

= 40.

= 70, 72.

Iris hartwegii

Iris virginica

Phenology Flowering Jun. Flowering May–Jun.
Habitat Yellow-pine forests on sunny or partially shaded slopes Wetlands, margins of lakes and streams
Distribution
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; DC; FL; GA; IA; IL; IN; KS; KY; LA; MD; MI; MN; MO; MS; NC; NE; NY; OH; OK; PA; SC; TN; TX; VA; WI; WV; ON; QC
[WildflowerSearch map]
[BONAP county map]
Discussion

Plants with pedicels 2.8–4.7 cm, and flowers light purple or bluish violet have been recognized as subsp. australis. Plants having a 3-flowered inflorescence unit, leaves about 1 cm wide, and pale yellow flowers with golden yellow veining have been called subsp. columbiana. Plants having both flowers open at the same time rather than consecutively, pedicels averaging only 1 cm, long narrow style arms and crests, and floral tubes 1.2–1.5 cm have been named subsp. pinetorum.

Iris hartwegii hybridizes with I. douglasiana, I. innominata, I. macrosiphon, I. munzii, I. tenax, and I. tenuissima. It is known from Butte County to Kern County.

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

Plants of Iris virginica from the southeastern and south-central states having stems 2–3-branched and seldom falling to the ground after flowering, and with capsules long-cylindric have been recognized as var. shrevei.

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

Source FNA vol. 26, p. 385. FNA vol. 26, p. 390.
Parent taxa Iridaceae > Iris > subg. Limniris > sect. Limniris > ser. Californicae Iridaceae > Iris > subg. Limniris > sect. Limniris > ser. Laevigatae
Sibling taxa
I. bracteata, I. brevicaulis, I. chrysophylla, I. cristata, I. douglasiana, I. fernaldii, I. fulva, I. germanica, I. giganticaerulea, I. hexagona, I. hookeri, I. innominata, I. lacustris, I. longipetala, I. macrosiphon, I. missouriensis, I. munzii, I. orientalis, I. pallida, I. prismatica, I. pseudacorus, I. pumila, I. purdyi, I. savannarum, I. setosa, I. sibirica, I. tenax, I. tenuis, I. tenuissima, I. tridentata, I. verna, I. versicolor, I. virginica
I. bracteata, I. brevicaulis, I. chrysophylla, I. cristata, I. douglasiana, I. fernaldii, I. fulva, I. germanica, I. giganticaerulea, I. hartwegii, I. hexagona, I. hookeri, I. innominata, I. lacustris, I. longipetala, I. macrosiphon, I. missouriensis, I. munzii, I. orientalis, I. pallida, I. prismatica, I. pseudacorus, I. pumila, I. purdyi, I. savannarum, I. setosa, I. sibirica, I. tenax, I. tenuis, I. tenuissima, I. tridentata, I. verna, I. versicolor
Synonyms I. hartwegii subsp. australis, I. hartwegii var. australis, I. hartwegii subsp. columbiana, I. hartwegii subsp. pinetorum, I. pinetorum I. caroliniana, I. georgiana, I. shrevei, I. virginica var. shrevei
Name authority Baker: Gard. Chron., n. s. 6: 323. (1876) Linnaeus: Sp. Pl. 1: 39. (1753)
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