Iris douglasiana

Herbert G. A. W. Arnott in W. J. Hooker and

in W. J. Hooker and G. A. W. Arnott, Bot. Beechey Voy., 395. 1840.

Common names: Mountain iris
IllustratedEndemic
Synonyms: Iris beecheyana Herbert Iris douglasiana var. alpha Dykes Iris douglasiana var. altissima Purdy ex Jepson Iris douglasiana var. beecheyana (Herbert) Baker Iris douglasiana var. bracteata Herbert Iris douglasiana var. major Torrey Iris douglasiana var. mendocinensis Eastwood Iris douglasiana var. nuda Herbert Iris douglasiana var. oregonensis R. C. Foster Iris watsoniana
Treatment appears in FNA Volume 26. Treatment on page 384. Mentioned on page 374, 381, 382, 385, 386, 387.

Rhizomes freely branching, forming large colonies, slender, 0.8–0.9 cm diam., covered with remains of old leaves; roots fibrous. Stems 1–4-branched, solid, 1.5–7 dm. Leaves: basal with blade yellow-green, occasionally darker green, sometimes flushed pink or red basally, prominently ribbed, linear, 4.5–10 dm × 2 cm, apex acute; cauline 1–3, reduced. Inflorescence units (2–) 3-flowered, branch units 2–3-flowered; spathes opposite or separated, divergent, green, sometimes flushed purple basally, lanceolate-acuminate, 6–12 cm × 7–12 mm. Flowers: perianth deep red-purple, lavender, gray-blue, cream, or white, with gold signal and blue or purple veins; floral-tube 1.5–2.8 cm, usually widening to bowl shape at base of flower; sepals oblanceolate to obovate, 5–9 × 1.4–3 cm, base gradually attenuate, apex obtusely rounded; petals oblanceolate, 4.5–7 × 0.9–1.8 cm, base attenuate to narrow claw; ovary elliptic-oval, sharply triangular in cross-section, 3–4 cm; style 1.7–3.5 cm; crests overlapping, subquadrate, 1–2 cm, margins coarsely toothed; stigmas triangular; pedicel 2–5 cm. Capsules sharply triangular in cross-section with ridge at each angle, tapering at both ends, remnant of floral-tube forming tip at apex, 2.5–5 cm. Seeds dark-brown, pyriform, wrinkled. 2n = 40.


Phenology: Flowering Apr–Jun.
Habitat: Open woods, sunny slopes and fields

Discussion

R. C. Foster (1937) named several varieties of Iris douglasiana, about which L. W. Lenz (1954) said, “This is a widespread and extremely variable species whose total variability is being increased due to introgressive hybridization between it and other species with which it has come into contact. Well marked and distinct geographic races cannot be detected; however, pronounced variations are to be found within a single population. For these reasons no attempt is made here to segregate taxa within such a polymorphic species.”

Iris douglasiana hybridizes with I. bracteata, I. chrysophylla, I. fernaldii, I. hartwegii, I. innominata, I. macrosiphon, I. munzii, I. purdyi, I. tenax, and I. tenuissima. The natural hybrid between I. douglasiana and I. innominata has been designated as Iris ×thompsonii R. C. Foster and the garden hybrid as Iris ×aureonympha E. H. English.

Selected References

None.

Lower Taxa

None.

"dm" is not declared as a valid unit of measurement for this property."decreasing" is not a number."widening" is not a number."dm" is not declared as a valid unit of measurement for this property.

... more about "Iris douglasiana"
dehiscing +  and latrorse +
Rounded (?) +  and Acute (?) +
Norlan C. Henderson +
Herbert G. A. W. Arnott in W. J. Hooker and +
red +, flushed pink +  and darker green +
2 cm20 mm <br />0.02 m <br /> (?) +
attenuate +
Iris subsect. Californicae +
yellow-green +
additional +
cordlike +
enlarging +
tapering +  and triangular +
Mountain iris +
overlapping +
subquadrate +
1cm +  and 2cm +
monochasial +
Calif. +  and Oreg. +
distinct or;partly completely connate +
hollow +  and solid +
1.5 cm15 mm <br />0.015 m <br /> (2.8 cm28 mm <br />0.028 m <br />) +
sessile +  and pedicellate +
fragrant +
upward-facing +
hollow +, solid +, branched +  and simple +
flattened +, terete +  and cordlike +
indehiscent +  and loculicidal +
woody;firm;cartilaginous +
Open woods, sunny slopes and fields +
multicellular +
distinct +
cauline +  and basal +
scale-like +
distinct +
conspicuous +
triangular +  and rounded +
triangular +  and elliptic-oval +
3 cm30 mm <br />0.03 m <br /> (4 cm40 mm <br />0.04 m <br />) +
2 cm20 mm <br />0.02 m <br /> (5 cm50 mm <br />0.05 m <br />) +
Purple (?) +, Blue (?) +, White (?) +, Cream (?) +, Gray-blue (?) +, Lavender (?) +, Red-purple (?) +  and Deep (?) +
4 cm40 mm <br />0.04 m <br /> (18 cm180 mm <br />0.18 m <br />) +
differentiated +
4.5 cm45 mm <br />0.045 m <br /> (7 cm70 mm <br />0.07 m <br />) +
reflexed +, spreading +  and erect +
reduced +
0.9 cm9 mm <br />0.009 m <br /> (?) +  and 1.8 cm18 mm <br />0.018 m <br /> (?) +
Flowering Apr–Jun. +
in W. J. Hooker and G. A. W. Arnott, Bot. Beechey Voy., +
2.5 cm25 mm <br />0.025 m <br /> (5 cm50 mm <br />0.05 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
heterogeneous +
tan;dark-brown +
conspicuously roughened +  and extensively corky +
4 +  and 20 +
wrinkled +
pyriform +
reflexed +  and spreading +
oblanceolate +  and obovate +
expanding +
1.4 cm14 mm <br />0.014 m <br /> (3 cm30 mm <br />0.03 m <br />) +
divergent +, separated +  and opposite +
flushed purple +  and green +
persisting +
lanceolate-acuminate +
0.7 cm7 mm <br />0.007 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
Illustrated +  and Endemic +
monochasial +
solid +  and 1-4-branched +
triangular +
3-lobed +  and filiform +
1.7 cm17 mm <br />0.017 m <br /> (?) +  and 3.5 cm35 mm <br />0.035 m <br /> (?) +
Iris beecheyana +, Iris douglasiana var. alpha +, Iris douglasiana var. altissima +, Iris douglasiana var. beecheyana +, Iris douglasiana var. bracteata +, Iris douglasiana var. major +, Iris douglasiana var. mendocinensis +, Iris douglasiana var. nuda +, Iris douglasiana var. oregonensis +  and Iris watsoniana +
Iris douglasiana +
Iris (sect. Limniris) ser. Californicae +
species +
connate +  and distinct +
scarious +
spathaceous +  and more-flowered +
obscure;prominent +
hardened +  and papery +
unequal +