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

Key to Rumex

View taxon page for Rumex

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

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

1. Flowers unisexual, on different plants (some flowers bisexual);    or  or base  generally jointed

2. Pedicels jointed distally; inner perianth  generally 1.2–1.7(2) mm, ± = fruit; leaf blade widely tapered or generally hastate or sagittate; from a creeping  and/or vertical taproot; CA-FP, GB ..... R. acetosella

2' Pedicels jointed near middle or proximally; inner perianth lobes 2.8–3.8 mm, > fruit; leaf blade base tapered; from a vertical taproot and densely tufted underground stolons; CaRH, SNH, MP, W&I ..... R. paucifolius

1' Flowers generally , sometimes also unisexual in 1 inflorescence; leaf blades not hastate or sagittate; pedicels jointed or not

3. Leaves caulinestems  to , generally with leafy  shoots below terminal inflorescence; leaf blade base tapered to ± rounded; inner perianth margins generally  (irregularly minutely notched, toothed)

4. Inner perianth lobes (20)23–30 mm wide; MP ..... R. venosus

4' Inner perianth lobes generally < 15 mm wide; MP, elsewhere

5. Perianth tubercles generally 0

6. Inner perianth  margin generally minute-toothed; inflorescence ± open; stems  (decumbent or ± erect); California (especially mtns, coast) ..... R. californicus

6' Inner perianth lobe margin generally entire; inflorescence dense; stems ascending or generally erect; c&s SNH, expected elsewhere ..... R. utahensis

5' Perianth tubercles >= 1

7. Perianth tubercle width < 1/3 inner lobe, if tubercle 1 then width >= 1/2 lobe

8. Plant terrestrial, submersed, or floating; taproot vertical or creeping; inner perianth lobes 2–2.5(3) mm, 1–1.5(2) mm wide, generally  or ; leaf  to lance-ovate, generally 3.5–5 × longer than wide; GB ..... R. lacustris

8' Plant terrestrial; taproot vertical; inner perianth lobes (2)2.5–3.5(4) mm, (2)2.5–3(3.5) mm wide, widely triangular; leaf  to lanceolate, generally 5–6 × longer than wide; CaRH, SN, ScV (Sutter Buttes), SnGb, GB ..... R. triangulivalvis

7' Perianth tubercle nearly as wide as inner lobe on at least 1 lobe

9. Leaf blade thick, leathery, lance-ovate to -elliptic or ovate-elliptic, <= 3.5 × as long as wide; inner perianth lobes (3)4–5 mm, (2.5)3–4 mm wide; perianth tubercle 1 ..... R. crassus

9' Leaf blade thick or generally thin, occasionally ± leathery, linear to lanceolate, generally > 3.5 × as long as wide; inner perianth lobes generally 2–4 mm, generally 1.5–3 mm wide; perianth tubercles 1 or 3

10. Inner perianth lobes (1.8)2–2.5(3) mm, tubercle 1, smooth to ± warty ..... R. salicifolius

10' Inner perianth lobes (2.5)3–4 mm, tubercles (1)3, generally smooth ..... R. transitorius

3' Leaves  and cauline (basal often withered when fruit mature); stem generally ± erect, generally unbranched below inflorescence; leaf blade base tapered to ; inner perianth margins entire or variously 

11. Perianth tubercles 0 or inconspicuous

12. Inner perianth lobes 11–16 mm; ocreae persistentroots tuber-like ..... R. hymenosepalus

12' Inner perianth lobes 5–10(12) mm; ocreae deciduous to partly persistent; roots not tuber-like ..... R. occidentalis

11' Perianth tubercles 1–3, conspicuous

13. Inner perianth lobe margin generally entire (if toothed or notched, teeth or notches < 0.3 mm)

14. Inner perianth lobe 2–3.5(4) mm, tubercle >= 1/3 its width; inflorescence ± open

15. Perennial herb; perianth tubercles ± equal, almost as wide as lobe ..... R. conglomeratus

15' Annual; perianth tubercles generally unequal, width ± 1/3 lobe ..... R. violascens (2)

14' Inner perianth lobe 3.5–7(7.5) mm, tubercle generally << 1/3 its width; inflorescence generally dense

16. Leaf blade 20–55(70) cm, margins flat to ± wavy; inner perianth lobe 4–7(7.5) mm;  5–13 mm, joint ±0; stem 8–15(20) dm ..... R. britannica

16' Leaf blade 15–30(35) cm, margin strongly wavy; inner perianth lobe 3.5–6 mm; pedicel (3)4–8 mm, joint swollen; stem 4–10(15) dm ..... R. crispus

13' Inner perianth lobe margin variously dentate, at least some teeth >= 0.3 mm

17. Annual, biennial

18. Inner perianth lobe 3–5.5(6) mm, teeth 1–3(5) mm ..... R. dentatus

18' Inner perianth lobe generally 1.5–3.5 mm, teeth 0.5–4 mm

19. Widest inner perianth lobe narrow-triangular or -kite-shaped, teeth 1–3 mm; inflorescence dense, bracts leaf-like

20. Perianth tubercle straw-colored, oblong-ovate, nearly as wide as inner lobe, tip ; inner perianth lobe teeth ± = width of lobe ..... R. persicarioides

20' Perianth tubercle ± brown or ± red, lance-linear to , <= 1/2 width of inner lobe, tip ± ; inner perianth lobe teeth generally 1.5–2.5(4) × width of lobe ..... R. fueginus

19' Widest inner perianth lobe widely ovate-triangular to ± , teeth <= 0.5 mm; inflorescence ± open, bracts ± not leaf-like ..... R. violascens (2)

17' Perennial herb

21. Leaf blade 20–40 cm, widely ovate to , base generally cordate; inner perianth lobe triangular to narrowly ovate-triangular ..... R. obtusifolius

21' Leaf blade 4–25(30) cm, generally oblong to lanceolate, base generally  or tapered; inner perianth lobe widely ovate-triangular to round-cordate

22. Inflorescence branches ; teeth of inner perianth lobe not wider at base, 0.3–2.5 mm ..... R. pulcher

22' Inflorescence branches ascending; teeth of inner perianth lobe wider at base, 0.2–1.5 mm

23. Inner perianth lobe 6–8(9) mm, round, base generally cordate, teeth 0.2–0.5 mm, each much wider at base ..... R. kerneri

23' Inner perianth lobe 3.5–5 mm, round- to triangular-ovate, base truncate or ± cordate, teeth 0.2–1.5 mm, each ± wider at base ..... R. stenophyllus


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

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