Iris pseudacorus

Linnaeus

Sp. Pl. 1: 38. 1753.

Common names: Yellow iris pale-yellow iris yellow flag yellow water iris fleur-de-lis iris jaune
IntroducedIllustrated
Treatment appears in FNA Volume 26. Treatment on page 390. Mentioned on page 374, 388.

Rhizomes pink, freely branching, producing extensive clumps, 2–3 cm diam., with fibrous remains of old leaves; roots fleshy. Stems usually 1-branched, solid, 7–15 dm. 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. Inflorescence units 4–12-flowered; spathes green with brown margins, outer spathe strongly keeled, inner without keel, 6–9 cm, subequal, margins not scarious. 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. Capsules prismatic to oblong-ovoid, obscurely 3-angled with obvious groove at each angle, 3.5–6 cm, beak 5 mm. Seeds D-shaped, flattened, 6–7 mm, corky, lustrous. 2n = 34.


Phenology: Flowering Apr–Jun.
Habitat: Swamps, wet shores of rivers and lakes

Distribution

Introduced; B.C., Man., N.B., Nfld. and Labr. (Nfld.), N.S., Ont., P.E.I., Que., Ala., Ark., Calif., Del., D.C., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Mass., Miss., N.H., N.Y., N.C., Ohio, Pa., R.I., S.C., Tenn., Va., Wash., W.Va., Eurasia, n Africa

Discussion

Selected References

None.

Lower Taxa

None.

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... more about "Iris pseudacorus"
dehiscing +  and latrorse +
Norlan C. Henderson +
Linnaeus +
recurved +  and erect +
attenuate +
Iris subsect. Laevigatae +
5 cm50 mm <br />0.05 m <br /> (?) +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
additional +
cordlike +
enlarging +
3-angled +, prismatic +  and oblong-ovoid +
3.5 cm35 mm <br />0.035 m <br /> (6 cm60 mm <br />0.06 m <br />) +
Yellow iris +, pale-yellow iris +, yellow flag +, yellow water iris +, fleur-de-lis +  and iris jaune +
laciniate +
1 cm10 mm <br />0.01 m <br /> (?) +  and 1.2 cm12 mm <br />0.012 m <br /> (?) +
monochasial +
B.C. +, Man. +, N.B. +, Nfld. and Labr. (Nfld.) +, N.S. +, Ont. +, P.E.I. +, Que. +, Ala. +, Ark. +, Calif. +, Del. +, D.C. +, Fla. +, Ga. +, Ill. +, Ind. +, Iowa +, Kans. +, Ky. +, La. +, Maine +, Mass. +, Miss. +, N.H. +, N.Y. +, N.C. +, Ohio +, Pa. +, R.I. +, S.C. +, Tenn. +, Va. +, Wash. +, W.Va. +, Eurasia +  and n Africa +
distinct or;partly completely connate +
hollow +  and solid +
ridged +  and terete +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
sessile +  and pedicellate +
fragrant +
upward-facing +
hollow +, solid +, branched +  and simple +
flattened +, terete +  and cordlike +
indehiscent +  and loculicidal +
woody;firm;cartilaginous +
Swamps, wet shores of rivers and lakes +
multicellular +
6 cm60 mm <br />0.06 m <br /> (9 cm90 mm <br />0.09 m <br />) +
distinct +
cauline +  and basal +
scale-like +
distinct +
conspicuous +
triangular +  and rounded +
not scarious +
triangular +
2.5 cm25 mm <br />0.025 m <br /> (7 cm70 mm <br />0.07 m <br />) +
bright-yellow +
4 cm40 mm <br />0.04 m <br /> (18 cm180 mm <br />0.18 m <br />) +
differentiated +
reflexed +, spreading +  and erect +
lanceolate +  and spatulate +
reduced +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
Flowering Apr–Jun. +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
heterogeneous +
tan;dark-brown +
conspicuously roughened +  and extensively corky +
4 +  and 20 +
flattened;d--shaped +
0.6 cm6 mm <br />0.006 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
cream colored +  and bright-yellow +
reflexed +  and spreading +
lanceolate +  and ovate or suborbiculate +
expanding +
3 cm30 mm <br />0.03 m <br /> (4 cm40 mm <br />0.04 m <br />) +
concave +
persisting +
W2 +, W1 +, Introduced +  and Illustrated +
monochasial +
solid +  and 1-branched +
3 cm30 mm <br />0.03 m <br /> (?) +  and 4 cm40 mm <br />0.04 m <br /> (?) +
Undefined subg. Limniris +
Iris pseudacorus +
Iris (sect. Limniris) ser. Laevigatae +
species +
connate +  and distinct +
scarious +
spathaceous +  and more-flowered +
obscure;prominent +
indehiscent +
hardened +  and papery +
unequal +