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PRE — Plant Risk Evaluator

Iris pseudacorus

by Ron Vanderhoff
Common Name(s)
pale yellow iris

Is this plant a cultivar?  No

Life History:  Perennial

Growth Form:  forb

Native to Africa, Temperate Asia, and Europe

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.

External Resources
GBIF Species Page
USDA Plants Database page
Tropicos Species Page
US National Germplasm Database
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Images

by Ron Vanderhoff
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by Ron Vanderhoff
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