Persicaria amphibia var. emersa (Michx.) J.C. Hickman (Michx.) J.C. Hickman
water smartweed (swamp smartweed)
Polygonaceae (Buckwheat family)
Introduction to Vascular Plants
water smartweed (swamp smartweed)
Polygonaceae (Buckwheat family)
Introduction to Vascular Plants
Map
Distribution of Persicaria amphibia var. emersa
Click here to view the full interactive map and legend
Introduction
Persicaria amphibia is a highly polymorphic aquatic species with two recognized but intergrading varieties in North America: var. emersa and var. stipulacea (Flora North America 2010). Both are widespread in the US and Canada, with a few exceptions in the northwest and southeast (USDA 2010). Plants which bloom in water, or are sometimes stranded on land during draw down periods, are recognized as var. stipulacea, while plants that bloom on moist soil are recognized as var. emersa (Flora North America 2010). Aside from habitat, characters that separate the two varieties include habit (erect or prostrate) and inflorescence shape.
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Species Information
General:
Perennial herb from a rhizome or stolon; stems prostrate and freely rooting to ascending, several, simple, with erect tips and flowering branches up to 30-80 cm tall/long.
Leaves:
Basal leaves lacking; stem leaves lanceolate to egg-shaped, usually floating, smooth above, hairy to smooth below, the blades 5-15 cm long, the stalks up to 1/2 as long as the blades; stipules smooth to hairy, cylindric, 1-2 cm long.
Flowers:
Inflorescence of 1 or 2 terminal or subterminal, spikelike panicles, 1-8 cm long, 1-2 cm wide; perianths scarlet to rose, 4-5 mm long, 5-lobed.
Fruits:
Achenes, lens-shaped, brown to black, smooth, shiny or sometimes dull, 2.5-3 mm long.
Notes:
Two intergrading varieties occur in BC:
1. Stalks usually glandular-hairy; inflorescence usually at least 4 cm long, cylindric................... var. emersa Michx.
1. Stalks usually smooth; inflorescence rarely 4 cm long, egg-shaped.................... var. stipulacea (Coleman) Fern.
Illustration
If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.
Illustration Source: The Illustrated Flora of British Columbia
Ecology
Ecological Framework for Persicaria amphibia var. emersa
The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)
The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)
| Site Information |
Value / Class |
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|
Avg |
Min |
Max |
|
| Elevation
(metres) |
933 | 55 | 2120 |
| Slope
Gradient (%) |
0 | 0 | 20 |
|
Aspect (degrees) |
119 | 0 | 186 |
| Soil
Moisture Regime (SMR) [0 - very xeric; 4 - mesic; 8 - hydric] |
7 | 1 | 8 |
| Modal
Nutrient Regime
Class |
D | ||
| #
of field plots species was recorded in: |
173 | ||
| Modal
BEC Zone Class |
IDF | ||
|
All BEC Zones (# of stations/zone) species was recorded in |
BAFA(1), BG(6), BWBS(5), CDF(2), CWH(1), ICH(7), IDF(81), MS(5), PP(9), SBPS(25), SBS(30) | ||
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Source:
Klinkenberg 2013
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Habitat and Range
Wet shorelines, ditches and shallow water in the lowland, steppe and montane zones; var. emersum - infrequent in S BC, rare northward to NE BC, var. stipulaceum - common throughout BC; N to AK, YT and NT, E to NF and S to FL, TX and CA.Status Information
Synonyms
Synonyms and Alternate Names:
Polygonum amphibium L.
Polygonum amphibium var. emersum Michx.