Iris douglasiana |
Iris brevicaulis |
|
---|---|---|
Douglas' iris, mountain iris |
short-stem iris, zigzag iris |
|
Rhizomes | freely branching, forming large colonies, slender, 0.8–0.9 cm diam., covered with remains of old leaves; roots fibrous. |
freely branching, producing extensive clumps, 1–2.5 cm diam. |
Stems | 1–4-branched, solid, 1.5–7 dm. |
declining or semi- erect, sharply zigzag, with short branch at each of 2–3 bends, leaf at every bend, flower bud at every bend, solid, 2.5–3 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. |
basal erect, spreading, or prostrate, blade deep green, ensiform, 3.5–7 dm × 1.5–3.5 cm, somewhat glaucous; cauline at each of 2–3 nodes, subtending and exceeding short branch and flower, blade 2–6 dm. |
Inflorescences/ |
(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. |
with terminal unit 2-flowered, each short branch unit 1-flowered; spathes foliaceous, lanceolate, 3–5 cm, subequal, apex acute; outer green, exceeding inner; inner partly scarious. |
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. |
perianth rich blue or blue-violet; floral tube funnelform, 1–2 cm; sepals ovate, 7.5–9 × 2.5–3 cm, base abruptly attenuate, claw light greenish yellow with darker veins, with prominent yellow midrib and large, yellow-white signal at union of limb and claw; petals erect or spreading-erect, lighter blue than sepals, oblanceolate, 5–6.5 × 1.5–2 cm; ovary prominently 6-angled, 1–1.3 cm; style greenish, 3.5–4 cm, crests reflexed, semiovoid to subquadrate, 1.2–1.5 cm, margins irregularly toothed or entire; stigmas 2-lobed, lobes rounded-deltoid; pedicel 1–1.3 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. |
hexagonal to almost circular in cross section with 6 equally placed ribs, with short beak at apex, 3–5 × 2–2.5 cm. |
Seeds | dark brown, pyriform, wrinkled. |
in 2 rows per locule, light brown, irregularly circular, flattened, 3–5 mm, very corky. |
2n | = 40. |
= 42, 44. |
Iris douglasiana |
Iris brevicaulis |
|
Phenology | Flowering Apr–Jun. | Flowering Apr–Jun. |
Habitat | Open woods, sunny slopes and fields | Open, rather moist woodlands |
Distribution |
CA; OR
|
AL; AR; FL; IL; IN; KS; KY; LA; MO; MS; OK; TN; ON
|
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. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Iris brevicaulis hybridizes with I. fulva to produce I. ×fulvala Dykes, and with I. giganticaerulea to produce I. ×flexicaulis Small. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 26, p. 384. | FNA vol. 26, p. 393. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | I. beecheyana, I. douglasiana var. alpha, I. douglasiana var. altissima, I. douglasiana var. beecheyana, I. douglasiana var. bracteata, I. douglasiana var. major, I. douglasiana var. mendocinensis, I. douglasiana var. nuda, I. douglasiana var. oregonensis, I. watsoniana | I. alabamensis, I. foliosa, I. mississippiensis |
Name authority | Herbert G. A. W. Arnott: in W. J. Hooker and G. A. W. Arnott, Bot. Beechey Voy., 395. (1840) | Rafinesque: Fl. Ludov., 20. (1817) |
Web links |