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Douglas' iris, mountain iris

Fernald's iris

Rhizomes

freely branching, forming large colonies, slender, 0.8–0.9 cm diam., covered with remains of old leaves;

roots fibrous.

many-branched, producing dense clumps, compact, slender, ca. 0.6 cm diam., base covered with remains of old leaves;

roots fibrous.

Stems

1–4-branched, solid, 1.5–7 dm.

simple, solid, 2–4 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 with blade gray-green, usually brilliantly colored basally, drying to unusual gray-green, veins fairly prominent, to 4 dm × 0.7–0.8 cm, often quite glaucous, margins not thickened;

cauline 2–several, spreading, sheathing stem for about 1/2 length, foliaceous, blade not inflated.

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.

2-flowered;

spathes opposite, connivent, often flushed red basally, broadly lanceolate, 5–9 cm × 6–11 mm, subequal.

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 pale creamy yellow with gold or gray veins;

floral tube funnelform, 3–6.2 cm, spreading apically to form wide throat;

sepals horizontally spreading, claw with deep yellow median line, oblanceolate to spatulate, 4.5–7 × 1–2 cm, base gradually attenuate into broad claw;

petals narrowly oblanceolate, 4.3–6 × 0.6–1.4 cm, base gradually attenuate into narrow claw;

ovary elliptical, nearly circular in cross section, 1.5–2.3 cm;

style 2.2–3 cm, crests divergent, linear to narrowly oblong, 1–1.7 cm;

stigmas triangular, margins entire;

pedicel 0.9–2.2 cm at anthesis.

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.

oblong, roundly trigonal, distinctly beaked, 2.5–3.5 cm.

Seeds

dark brown, pyriform, wrinkled.

dark brown, wrinkled.

2n

= 40.

= 40.

Iris douglasiana

Iris fernaldii

Phenology Flowering Apr–Jun. Flowering Apr–Jul.
Habitat Open woods, sunny slopes and fields Mixed evergreen forest
Distribution
from FNA
CA; OR
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
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 fernaldii hybridizes with I. douglasiana, I. innominata, and I. macrosiphon.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 26, p. 384. FNA vol. 26, p. 387.
Parent taxa Iridaceae > Iris > subg. Limniris > sect. Limniris > ser. Californicae Iridaceae > Iris > subg. Limniris > sect. Limniris > ser. Californicae
Sibling taxa
I. bracteata, I. brevicaulis, I. chrysophylla, I. cristata, 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
I. bracteata, I. brevicaulis, I. chrysophylla, I. cristata, I. douglasiana, 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 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
Name authority Herbert G. A. W. Arnott: in W. J. Hooker and G. A. W. Arnott, Bot. Beechey Voy., 395. (1840) R. C. Foster: Iridis Sp. Nov., 1. (1938)
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