Epilobium palustre

Linnaeus

Sp. Pl. 1: 348. 1753.

Common names: Marsh willowherb épilobe palustre
Synonyms: Chamaenerion palustre (Linnaeus) Schreber Epilobium molle var. sabulonense Fernald E. nesophilum var. lupulinum Hodgdon & R. B. Pike E. nesophilum var. sabulonense (Fernald) Fernald E. oliganthum Michaux E. palustre var. albescens Wahlenberg E. palustre var. grammadophyllum (Haussknecht) Munz E. palustre var. lapponicum Wahlenburg E. palustre var. longirameum Fernald & Wiegand E. palustre var. oliganthum (Michaux) Fernald E. palustre var. sabulonense (Fernald) B. Boivin E. pylaieanum Fernald E. wyomingense A. Nelson
Treatment appears in FNA Volume 10.
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Herbs with multiple filiform epigeous stolons with widely spaced, small leaves, terminating in condensed, dark, small turions 3–7 × 2–3 mm. Stems erect, loosely clustered, terete, 5–80 cm, simple to well branched, subglabrous on proximal internodes, sometimes with faint strigillose lines decurrent from margins of petioles, densely strigillose distally. Leaves opposite proximal to inflorescence, alternate distally, subsessile; blade lanceolate or narrowly elliptic to sublinear, 1.5–7 × 0.2–1.9 cm, base cuneate, margins entire or inconspicuously denticulate, 2–6 teeth per side, veins inconspicuous, apex acute or acuminate, surfaces strigillose abaxially, subglabrous adaxially or strig­illose only on margins and veins; bracts smaller and narrower. Inflorescences nodding in bud, later erect, racemes, not branched, densely strigillose, rarely mixed sparsely glandular puberulent. Flowers erect to spreading; buds 2–5 × 1.5–2.5 mm; pedicel 8–12 mm; floral-tube 0.6–1.8 × 1.3–2.2 mm, ring of spreading hairs at mouth inside; sepals 1.4–4.5 × 0.8–1.5 mm, abaxial surface strigillose; petals usually white, rarely pink, 2–9 × 1.8–5 mm, obcordate, apical notch 0.6–1.6 mm; filaments cream or white, those of longer stamens 0.8–3.5 mm, those of shorter ones 0.4–2.1 mm; anthers 0.4–1 × 0.3–0.7 mm; ovary 12–35 mm, strigillose; style cream, 1.5–4.5 mm, stigma clavate to cylindrical, entire, 0.8–2 × 0.5–1.4 mm, usually surrounded by, rarely exserted beyond, anthers. Capsules straight or upcurved, 25–90 mm, surfaces strigillose; pedicel 15–35 (–60) mm. Seeds elliptic, attenuate to narrowly fusiform, 1.4–2.2 × 0.4–0.5 mm, chalazal collar 0.1–0.25 mm, conspicuous, surface finely papillose; coma persistent, white, 5–7 mm. 2n = 36.


Phenology: Flowering Jul–Sep.
Habitat: Low, boggy areas, swamps, saturated stream banks, mossy meadows.
Elevation: 0–1000(–2600) m.

Distribution

Greenland, St. Pierre and Miquelon, Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., N.S., Nunavut, Ont., P.E.I., Que., Sask., Yukon, Alaska, Calif., Colo., Conn., Maine, Mass., Mich., Minn., Mont., N.H., N.J., N.Y., Oreg., Pa., R.I., S.Dak., Utah, Vt., Wis., Wyo., n, c Eurasia

Discussion

Epilobium palustre is an extremely widespread circumboreal species that is relatively common from Alaska across Canada, especially around the Great Lakes to the Maritime provinces (mostly below 1000 m). This species is somewhat less common in the north­eastern United States, and only scattered in the moun­tains of the western United States, south to California and Colorado (to 3000 m). It also occurs in ice-free regions of Greenland south of 70º north latitude, in northern and central Europe, across most of subarctic Russia to the Caucasus, the Himalaya complex, and eastern Asia, including Japan and the Russian Far East.

Epilobium palustre shows considerable variation across its very wide distribution and, not surpris­ingly, distinctive local races, which sometimes have been named formally, including several from north­eastern North America. Within series Palustriformes by C. Haussknecht (1884), M. L. Fernald (1944d) clari­fied much confusion in names at that time, clearly deline­ating and establishing the nomenclature of E. davuricum, E. leptophyllum, E. palustre, and E. densum. Fernald also recognized E. nesophilum (see discussion under 18. E. leptophyllum) and E. pylaieanum, the latter based on small plants of E. palustre from southern Newfoundland.

Epilobium lineare Muhlenberg and E. palustre var. albiflorum Lehmann are illegitimate names that per­tain here.

Selected References

None.

Lower Taxa

None.

"narrower" is not a number.

... more about "Epilobium palustre"
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
subequal +  and longer +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
acuminate +  and acute +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.16 cm1.6 mm <br />0.0016 m <br />) +
Peter C. Hoch +
Linnaeus +
cuneate +
indehiscent +  and loculicidal +
1.5 cm15 mm <br />0.015 m <br /> (7 cm70 mm <br />0.07 m <br />) +
toothed +  and entire +
narrowly elliptic +  and sublinear +
0.2 cm2 mm <br />0.002 m <br /> (1.9 cm19 mm <br />0.019 m <br />) +
smaller +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
recurved +  and erect +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
sessile +  and pedicellate +
narrowly subcylindric +  and narrowly clavate +
2.5 cm25 mm <br />0.025 m <br /> (9 cm90 mm <br />0.09 m <br />) +
sessile +  and pedicellate +
persistent +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
Marsh willowherb +  and épilobe palustre +
Greenland +, St. Pierre and Miquelon +, Alta. +, B.C. +, Man. +, N.B. +, Nfld. and Labr. +, N.W.T. +, N.S. +, Nunavut +, Ont. +, P.E.I. +, Que. +, Sask. +, Yukon +, Alaska +, Calif. +, Colo. +, Conn. +, Maine +, Mass. +, Mich. +, Minn. +, Mont. +, N.H. +, N.J. +, N.Y. +, Oreg. +, Pa. +, R.I. +, S.Dak. +, Utah +, Vt. +, Wis. +, Wyo. +, n +  and c Eurasia +
0–1000(–2600) m. +
basifixed +  and versatile +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
1.3mm +  and 2.2mm +
actinomorphic +
erect +  and spreading +
sessile +  and pedicellate +
curved +  and straight +
4-angled +, terete +, narrowly cylindrical +  and fusiform or rarely narrowly ellipsoidal +
slender +
Low, boggy areas, swamps, saturated stream banks, mossy meadows. +
perennial +  and annual +
suffrutescent +
erect +  and nodding +
alternate +, opposite +  and spaced +
deciduous +
strigillose +
decurrent +
denticulate +  and entire +
strigillose +
1.2 cm12 mm <br />0.012 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
numerous +  and 1 +
multicellular +
3.5 cm35 mm <br />0.035 m <br /> (6 cm60 mm <br />0.06 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
pink +  and white +
2mm +  and 9mm +
obcordate +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Flowering Jul–Sep. +
puberulent +  and strigillose +
inflated +
basal +  and cauline +
clavate +  and globose +
0.14 cm1.4 mm <br />0.0014 m <br /> (0.22 cm2.2 mm <br />0.0022 m <br />) +
sculptured +  and smooth +
attenuate +  and narrowly fusiform +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
lanceolate +, , +, flushed with red or flushed with cream +  and green +
deciduous +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
parenchymatous +
parietal +, axile +  and placentation +
unequal +
aquatic +, amphibious +  and terrestrial +
white +  and cream +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.21 cm2.1 mm <br />0.0021 m <br />) +
2 times as many as sepals +
branched +  and simple to well +
prostrate +  and decumbent +
strigillose +  and subglabrous +
exfoliating +
5 cm50 mm <br />0.05 m <br /> (80 cm800 mm <br />0.8 m <br />) +
not woody +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
clavate +  and cylindrical +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.14 cm1.4 mm <br />0.0014 m <br />) +
subsessile +  and petiolate +
intrapetiolar +
filiform +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
aquatic +, amphibious +  and terrestrial +
strigillose +  and subglabrous +
papillose +
constricted +
Chamaenerion palustre +, Epilobium molle var. sabulonense +, E. nesophilum var. lupulinum +, E. nesophilum var. sabulonense +, E. oliganthum +, E. palustre var. albescens +, E. palustre var. grammadophyllum +, E. palustre var. lapponicum +, E. palustre var. longirameum +, E. palustre var. oliganthum +, E. palustre var. sabulonense +, E. pylaieanum +  and E. wyomingense +
Epilobium palustre +
Epilobium sect. Epilobium +
species +
3(-5)-aperturate +
0.3 cm3 mm <br />0.003 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
inconspicuous +