OregonFlora: Iris giganticaerulea vs. Iris douglasiana

	Iris giganticaerulea	Iris douglasiana
		Douglas iris
Habit		Herbs 20–80 cm tall.
Roots		fibrous; rhizomes slender, freely branching, covered with old leaf bases, forming large colonies.
Stems		sometimes branched.
Leaves		evergreen; to 22 mm wide; shiny yellow-green above; duller green below, often red or purple basally; cauline leaves reduced.
Inflorescences		2–3-flowered; bracts opposite or separate; open or closed, 5–10 cm long.
Flowers		red-purple, lavender, gray-blue, cream, or white, with gold signal and blue or purple veins; floral tube 10–28 mm long, usually widening to bowl shape; style tips rounded to oblong, reflexed, overlapping; and coarsely toothed; stigmas triangular.
Fruits		sharply triangular in cross section; angles ridged, with nipple-like projection above.
Seeds		pear-shaped, dark brown, wrinkled.
2n		=40.

	Iris giganticaerulea	Iris douglasiana
Distribution	[WildflowerSearch map] [BONAP county map]	[WildflowerSearch map] [BONAP county map]
Discussion		Coastal habitats, open woods, and fields. Flowering Mar–Jul. 0–400 m. CR, Est, Sisk. CA. Native. The leaves of I. douglasiana are unpalatable to livestock, and the species is considered a noxious weed in pastures. In Oregon, I. douglasiana hybridizes with I. bracteata, I. chrysophylla, I. innominata, and I. tenax. In California, it hybridizes with I. tenuissima, I. fernaldii, I. hartwegii, I. macrosiphon, I. munzii, and I. purdyi. Cultivars have been developed for the nursery trade from some of these hybrids.
Source		Flora of Oregon, volume 1, page 260 Ann Willyard
Sibling taxa	I. bracteata, I. chrysophylla, I. douglasiana, I. germanica, I. innominata, I. missouriensis, I. pseudacorus, I. tenax, I. tenuis, I. tenuissima	I. bracteata, I. chrysophylla, I. germanica, I. innominata, I. missouriensis, I. pseudacorus, I. tenax, I. tenuis, I. tenuissima
Synonyms		Iris douglasiana var. oregonensis
Web links	Local Web sites: Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: CA, OR Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria, Turner Photog. WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Iris giganticaerulea

Iris douglasiana

Douglas iris

Habit

Herbs 20–80 cm tall.

Roots

fibrous;

rhizomes slender, freely branching, covered with old leaf bases, forming large colonies.

Stems

sometimes branched.

Leaves

evergreen; to 22 mm wide; shiny yellow-green above; duller green below, often red or purple basally;

cauline leaves reduced.

Inflorescences

2–3-flowered;

bracts opposite or separate; open or closed, 5–10 cm long.

Flowers

red-purple, lavender, gray-blue, cream, or white, with gold signal and blue or purple veins;

floral tube 10–28 mm long, usually widening to bowl shape;

style tips rounded to oblong, reflexed, overlapping; and coarsely toothed;

stigmas triangular.

Fruits

sharply triangular in cross section; angles ridged, with nipple-like projection above.

Seeds

pear-shaped, dark brown, wrinkled.

=40.

Iris giganticaerulea

Iris douglasiana

Distribution

[WildflowerSearch map]

[BONAP county map]

[WildflowerSearch map]

[BONAP county map]

Discussion

Coastal habitats, open woods, and fields. Flowering Mar–Jul. 0–400 m. CR, Est, Sisk. CA. Native.

The leaves of I. douglasiana are unpalatable to livestock, and the species is considered a noxious weed in pastures. In Oregon, I. douglasiana hybridizes with I. bracteata, I. chrysophylla, I. innominata, and I. tenax. In California, it hybridizes with I. tenuissima, I. fernaldii, I. hartwegii, I. macrosiphon, I. munzii, and I. purdyi. Cultivars have been developed for the nursery trade from some of these hybrids.