Key to Persicaria

View taxon page for Persicaria

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

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

1. Inflorescence ± head-like; 

petioles 

Leaf stalk, connecting leaf blade to stem; sometimes more or less indistinct.

generally winged, ear-like 

lobes 

1. A major expansion or bulge, such as on the margin of a leaf, sepal, or petal, or on the surface of an ovary. 2. The free tips of otherwise fused structures, such as sepals or petals; larger than teeth.

at base (sect. Cephalophilon) ..... P. capitata

1' Inflorescence spike- or panicle-like; petioles not winged, ear-like lobes 0

2. Inflorescence panicle-like; perianth 

rotate 

Wheel-shaped, spreading, or saucer-shaped; often applied to a fused corolla with a short or nonexistent tube and a spreading limb.

, parts fused < 1/5 (sect. Rubrivena) ..... P. wallichii

2' Inflorescence spike-like; perianth bell-shaped or ± so, parts fused > 1/3 (sect Persicaria)

3. Perianth gland-dotted

4. Perianth 

lobe 

1. A major expansion or bulge, such as on the margin of a leaf, sepal, or petal, or on the surface of an ovary. 2. The free tips of otherwise fused structures, such as sepals or petals; larger than teeth.

 margins ± red; fruit dull; leaves bitter-tasting ..... P. hydropiper

4' Perianth lobe margins generally white; fruit shiny; leaves not bitter-tasting ..... P. punctata

3' Perianth not gland-dotted

5. Perennial herb, generally rhizomed or stoloned

6. Inflorescence terminal, 1 or paired, 8–20 mm wide; styles 2; fruit lens-shaped ..... P. amphibia

6' Inflorescence 

axillary 

Pertaining to or within an axil, especially a leaf axil.

, terminal, 2 or more, 2–5 mm wide; styles 3; fruit 3-angled ..... P. hydropiperoides

5' Annual, rhizomes or stolons 0

7. Ocreae leaf-like distally ..... [P. orientalis]

7' Ocreae papery throughout

8. Peduncle glands 0; bristles 2–3.5(4.5) mm on ocrea margins ..... P. maculosa

8' Peduncle glands ± stalked; bristles 0 or < 1 mm on ocrea margins

9. Perianth lobes 4(5), outer with anchor-shaped veins; inflorescence generally ± nodding ..... P. lapathifolia

9' Perianth lobes 5, outer without anchor-shaped veins; inflorescence generally 

erect 

Upright; vertically oriented.

..... P. pensylvanica

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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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