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fleur-de-lis, horticultural iris, iris jaune, pale-yellow iris, yellow flag, yellow iris, yellow water iris

crested iris, dwarf crested iris

Rhizomes

pink, freely branching, producing extensive clumps, 2–3 cm diam., with fibrous remains of old leaves;

roots fleshy.

producing fleshy roots, and 2–8 cordlike branches at apex, cordlike portion 2–3 dm × 1–2 mm, gradually enlarging to 8–12 mm diam., nodes with brown, scalelike leaves and rarely roots.

Stems

usually 1-branched, solid, 7–15 dm.

simple, 2.5–4.5 cm.

Leaves

basal deciduous, at first erect, then recurved, blade dark green, with prominent median thickening, 4–10 dm × 2–3 cm, slightly glaucous basally;

cauline equaling inflorescence unit.

basal 6–8, proximal 2–3 sheathing, blade light brown with darker brown line along midrib at base, falcate, scarious, distal 4–5 not sheathing, blade green or yellowish green, with few, subprominent veins, broadly ensiform, slightly falcate, to 1.5 dm × 1–2.5 cm, enlarging to 4 dm after anthesis;

cauline 2–3, sheathing, proximal very similar to basal leaves, distal 1 or 2 reduced, herbaceous, blade falcate, not inflated.

Inflorescence units

4–12-flowered;

spathes green with brown margins, outer spathe strongly keeled, inner without keel, 6–9 cm, subequal, margins not scarious.

1–2-flowered;

spathes green, sharply keeled, somewhat inflated, 2–6 cm, unequal, outer shorter than inner.

Flowers

perianth bright yellow;

floral tube 0.6–0.8 cm, with no constriction into ovary;

sepals bright yellow or cream colored, lanceolate to ovate or suborbiculate, 5–7.5 × 3–4 cm, base abruptly attenuate, claw ca. 1/2 length of limb, signal a darker yellow basal patch limited by short, brown lines;

petals without veining, lanceolate to spatulate, 2–3 cm;

ovary triangular in cross section with concave sides and narrow groove at each angle, 1.5 cm;

style keeled, 3–4 cm, crests spreading, 1–1.2 cm, laciniate at apex;

stigmas rounded with prominent tongue;

pedicel 2.5–7 cm.

perianth blue, lilac-purple, or white;

floral tube filiform, widening distally, 4–8 cm, lifting expanded portion of flower out of spathes;

sepals spreading, with 3 parallel, toothed, crested ridges on white signal bordered with purple, tapering gradually into claw, 3–6 × 1.5–2.5 cm, base gradually attenuate, apex rounded, emarginate;

petals spreading, same color as sepals, oblanceolate, 3–4 × 1–2 cm;

ovary triangular, with shallow groove along each face, 0.6–1 cm;

style 1.5 cm, crests narrowly triangular, 6–9 mm;

stigmas oblong, margins entire;

pedicel 0.7–1.8 cm.

Capsules

prismatic to oblong-ovoid, obscurely 3-angled with obvious groove at each angle, 3.5–6 cm, beak 5 mm.

usually enclosed in spathes, oval, sharply triangular, each angle ridged, 1–1.5 cm.

Seeds

D-shaped, flattened, 6–7 mm, corky, lustrous.

yellowish brown, 3.2–3.5 mm, smooth, with narrow, white appendage wrapped around seed, 3.4–4 mm, quickly drying upon exposure to air.

2n

= 34.

= 24, 32.

Iris pseudacorus

Iris cristata

Phenology Flowering Apr–Jun. Flowering Apr–Jul.
Habitat Swamps, wet shores of rivers and lakes Rich woods, ravines, bluffs, usually in calcareous soil
Distribution
from FNA
AL; AR; CA; DC; DE; FL; GA; IA; IL; IN; KS; KY; LA; MA; ME; MS; NC; NH; NY; OH; PA; RI; SC; TN; VA; WA; WV; BC; MB; NB; NF; NS; ON; PE; QC; Eurasia; n Africa [Introduced in North America]
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; DC; GA; IA; IL; IN; KY; MD; MO; MS; NC; OH; OK; PA; SC; TN; VA; WV
[WildflowerSearch map]
[BONAP county map]
Source FNA vol. 26, p. 390. FNA vol. 26, p. 377.
Parent taxa Iridaceae > Iris > subg. Limniris > sect. Limniris > ser. Laevigatae Iridaceae > Iris > subg. Limniris > sect. Lophiris
Sibling taxa
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. 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. 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, I. virginica
Synonyms Neubeckia cristata
Name authority Linnaeus: Sp. Pl. 1: 38. (1753) Solander ex Aiton: Hort. Kew. 1: 70. (1789)
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