The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

prairie iris, savanna iris

Clackamas iris

Rhizomes

greenish, freely branching, forming large, open clumps, 2–2.5 cm diam., fleshy, with fibrous bases of old leaves not covering rhizome but persisting on ringlike scars.

superficial or very shallow, cordlike portion 1–2 dm × 2 mm, expanding to 10–15 mm diam., nodes with brown, scalelike leaves and few to no roots.

Stems

1-branched, solid, 3–10 dm.

1–2-branched, 3–3.2 dm.

Leaves

basal usually dying back shortly after anthesis, blade bright green, 6–10 dm × 0.8–2 cm, sometimes glaucescent;

cauline with blade elongate, linear-attenuate, 15–20 cm, exceeding flowers.

basal with blade pale green, 3.2 dm × 1.5 cm, margins scarious basally, apex acute, proximal 2 semi- sheathing, blade 5 cm, scarious;

cauline 1–2, sheathing branch and stem for ca. 1/2 their length, blade ca. 5 cm, semimembranous.

Inflorescences/Inflorescence units

1–3-flowered, branch units 1–2-flowered;

spathes lanceolate, subequal or unequal, apex acute;

outer 8–10 cm, herbaceous, margins scarious;

inner 6–9 cm, completely scarious.

2–3-branched, each unit with single flower, all borne at approximately the same level;

spathes 2–3 cm × 5 mm, subequal, scarious except basally and along midrib.

Flowers

perianth blue to blue-violet (white in forma albispiritis);

floral tube funnelform, 1.2–1.5 cm;

sepals blue or pale violet with flecks of white and lines of deeper blue on either side of ridge, spatulate, elliptic to ovate, 7–8 cm, apex acuminate, ridge yellow, linear, extending to about middle of limb, finely pubescent, claw light green, striated, ribbed, 1–1.2 cm;

petals erect or spreading-erect, deep blue, linear to narrowly linear-spatulate, 6–7.5 cm, base abruptly attenuate into claw, claw channeled, green with darker lines, margins pale;

ovary bluntly 3-angled, ridged at each angle and on faces between angles;

style linear-acute, 5–6 cm;

crests ovate, 1–2 cm, margins sharply and irregularly toothed;

stigmas broadly 2-lobed, margins crenate;

pedicel 1.6–2 cm.

perianth white or blue tinged with deep violet lines;

floral tube funnelform, 0.3 cm;

sepals oblong-spatulate, 2.8 × 1 cm, apex deeply emarginate, signal an inconspicuous crest with low, yellow, undissected ridge;

petals bluish white, oblanceolate-spatulate, base gradually attenuate into claw;

ovary elliptical, 0.4–0.7 cm;

style 1.8 cm, crests broadly obovate, 0.7 cm, margins erose;

stigmas triangular-acuminate, margins entire;

pedicel 0.4–1 cm, not lifting flower clear of spathes.

Capsules

ellipsoid, round in cross section, roundly 6-lobed, with 6 sharp, winglike, equally spaced ridges converging to form stout beak at apex, 6–10 cm, dehiscence loculicidal.

depressed-globose, roundly triangular, 0.9–1.5 × 1.2 cm.

Seeds

in 1 row per locule, brown, circular or uneven, flattened, 8–12 mm diam, very corky.

pale brown, with whitish raphe, D-shaped, pitted.

2n

= 44.

= 28.

Iris savannarum

Iris tenuis

Phenology Flowering late Mar–early Apr. Flowering May.
Habitat Wet ditches, margins of lakes, streams, and swamps Open, wooded slopes in leafy soil with Douglas fir and dense shrubs
Distribution
from FNA
AL; FL; GA
[WildflowerSearch map]
[BONAP county map]
from FNA
OR
[BONAP county map]
Discussion

Iris savannarum has often been included in I. hexagona, but differs in several ways. The capsules of I. hexagona are more obviously hexagonal, with smooth faces alternating with those that have two rounded lobes, whereas the capsules of I. savannarum are more rounded but with six obvious ridges, almost of winglike proportions. Iris hexagona has yellow-green leaves instead of the brighter green of I. savannarum. The leaves of I. savannarum die back after anthesis, while those of I. hexagona remain green. The flowering period of I. savannarum is almost one month earlier than that of I. hexagona in the area where both are known to grow. The sepals of I. savannarum are more acute at the apex than those of I. hexagona.

Iris savannarum has been hybridized with Iris fulva to produce I. ×cacique (J. Berry) N. C. Henderson.

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

Of conservation concern.

Iris tenuis was originally placed in ser. Californicae, but R. C. Foster (1937) stated, “It is with some hesitation that I leave it in association with them. The broad, pale green leaves are much like those of a giant I. cristata.” F. H. Smith and Q. D. Clarkson (1956) said, “It clearly does not belong in the subsection with the other members of the Californicae,” and Clarkson in a later treatment (1958) created a new subsection, the Oregonae, for it. L. W. Lenz (1959b) moved this species into subsect. Evansia (= sect. Lophiris), with which it shows many relationships.

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

Source FNA vol. 26, p. 393. FNA vol. 26, p. 378.
Parent taxa Iridaceae > Iris > subg. Limniris > sect. Limniris > ser. Hexagonae Iridaceae > Iris > subg. Limniris > sect. Lophiris
Sibling taxa
I. bracteata, I. brevicaulis, I. chrysophylla, I. cristata, I. douglasiana, 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. 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. 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. tenuissima, I. tridentata, I. verna, I. versicolor, I. virginica
Synonyms I. albispiritus, I. hexagona var. savannarum, I. kimballiae, I. rivularis
Name authority Small: Addisonia 9: 57, plate 317. (1925) S. Watson: Proc. Amer. Acad. Arts 17: 380. (1882)
Web links