Jepson eFlora: Key page
Vascular Plants of California
Key to families | Table of families and genera

Key to Iris

View taxon page for Iris

(For a list of species in Iris, use the above link.)

Jepson Manual glossary definitions can be seen by moving your cursor over words underlined with dots.

1. Sepal obviously bearded ..... I. germanica

1' Sepal not obviously bearded

2. Perianth tube > 30 mm

3. Cauline leaves bract-like

4. Perianth pale cream-yellow with prominent brown-violet veins, rose-violet with darker veins, or ± white with rose veins; stigmas , ± rounded, or 2-lobed ..... I. purdyi

4' Flowers pale yellow or cream with same color (or ± red) veins; stigmas triangular or tongue-shaped ..... I. tenuissima subsp. purdyiformis

3' Cauline leaves similar to 

5. Stigmas tongue-shaped, tip rounded;  2–5 mm diam

6. Stigmas perianth parts  or narrowly elliptic; stem generally < 1 dm ..... I. chrysophylla

6' Stigmas finely toothed; perianth parts widely oblanceolate; stem >= 1 dm ..... I. tenuissima subsp. tenuissima

5' Stigmas triangular, tip ; rhizome 4–9 mm diam

7. Perianth tube ; basal leaves >= 6 mm wide ..... I. fernaldii

7' Perianth tube abruptly inflated at top (bowl-like); basal leaves <= 6 mm wide ..... I. macrosiphon

2' Perianth tube < 30 mm

8. Stigmas 2-lobed; rhizomes 9–30 mm diam; cauline leaves bract-like for at least 2/3 length

9. Lowest bracts ; moist, coastal prairie or open coastal forest; flowers 3–6, lilac-purple ..... I. longipetala

9' Lowest bracts ; seasonally wet sites; flowers 1–2, pale lilac to ± white, or 2–9, brown, red-brown, or green

10. Basal leaves 25–35 mm wide; bracts not scarious; flowers 2–9, pale yellow to brown, red-brown, or green, veined green or red-brown ..... I. foetidissima

10' Basal leaves 3–9 mm wide; bracts generally scarious; flowers 1–2, pale lilac to ± white, veined lilac-purple ..... I. missouriensis

8' Stigmas triangular, tongue-shaped, or rounded; rhizomes 1–12 mm or 30–40 mm diam; cauline leaves bract-like or similar to basal

11. Stigmas rounded; basal leaves 20–35 mm wide; rhizomes 30–40 mm diam; wetlands ..... I. pseudacorus

11' Stigmas triangular or tongue-shaped; basal leaves 2–20 mm wide; rhizomes 1–12 mm diam; dry slopes (moist meadows)

12. Cauline leaves bract-like for at least 2/3 of length

13. Perianth tube <= 10 mm; cauline leaves overlapped; flowers generally 2 ..... I. bracteata

13' Perianth tube > 10 mm; cauline leaves generally not overlapped; flowers 1–2

14. Lowest bracts ovary triangular, clearly winged

15. Ovary clearly winged; perianth with deep maroon or ± brown veins ..... I. tenax subsp. klamathensis

15' Ovary triangular but not winged; perianth lacking dark veins ..... I. hartwegii subsp. pinetorum

14' Lowest bracts enclosing perianth tube; ovary rounded or triangular, not winged

16. Flowers generally golden yellow; ovary rounded; petals elliptic ..... I. innominata

16' Flowers generally lavender to blue, occasionally ± white; ovary triangular; petals obovate ..... I. thompsonii

12' Cauline leaves similar to basal

17. Flowers pale cream to yellow or gold-yellow, veined gold or bright yellow or not

18. Flowers 3; outer  9–15 cm; perianth tube 11–15 mm ..... I. hartwegii subsp. columbiana

18' Flowers 2; outer bract 6–11 cm; perianth tube 5–10 mm ..... I. hartwegii subsp. hartwegii

17' Flowers blue to lavender or purple (white or pale cream), with cream or ± white throat or not

19. Basal leaves 7–10 mm wide; flowers 2; dry slopes ..... I. hartwegii subsp. australis

19' Basal leaves 10–22 mm wide; flowers generally > 2; grassy sites

20. Stem generally branched, flowers 2/branch; coastal plains ..... I. douglasiana

20' Stem unbranched, flowers 3; wet grassy sites in s SN ..... I. munzii


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Citation for the whole project: Jepson Flora Project (eds.) . Jepson eFlora, [accessed on ]

Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on .

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