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codlins-and-cream, fiddle grass, fiddle grass willowherb, great or great hairy willowherb, great willowherb, hairy willlowherb, hairy willow-herb, épilobe hirsute

dwarf willowherb, obscure willow-herb

Habit Herbs usually robust and rank, sometimes woody near base, with thick, ropelike stolons to 1 m with scattered cataphylls and, often, terminal leafy rosette. Herbs with elongated, leafy epigeal stolons.
Stems

erect to ascending, often clumped, terete, 25–120(–250) cm, unusually thick, 3–9 mm diam., well branched mainly in distal 1/2, densely long-villous throughout, usually mixed glandular puberulent distally, rarely sparsely villous or densely white-tomentose.

erect or ascending, subterete, 20–80 cm, often well branched from base, sometimes also distally, subglabrous proximal to inflorescence with raised strigillose lines decurrent from margins of petioles, strigillose distally.

Leaves

opposite proximal to inflorescence, alternate distally, sessile and ± clasping stem;

blade elliptic-lanceolate to narrowly obovate or elliptic, 4–12(–23) × 0.3–4(–5) cm, base cuneate to attenuate, margins serrulate, 15–50 teeth per side, veins 6–9 per side, apex acute to acuminate or obtuse proximally, surfaces ± densely villous;

bracts moderately reduced.

opposite proximal to inflorescence, alternate distally, petiole 0–2 mm;

blade green or slightly bluish green, lanceolate to narrowly ovate, 1.5–10 × 0.4–1.8 cm, ± shorter than internodes, base rounded to attenuate, margins denticulate with 15–40 evenly spaced teeth per side, veins prominent, 3–7 per side, apex subacute, surfaces sparsely strigillose, mainly on margins and veins;

bracts gradually reduced.

Inflorescences

erect racemes or panicles, usually densely villous and glandular puberulent, rarely tomentose.

erect racemes or sparse panicles, strigillose.

Flowers

erect;

buds 5–9 × 1.8–4.5 mm, sometimes beaked;

pedicel 3–11 mm;

floral tube 1.3–2.9 × 2.2–4 mm, conspicuous ring of spreading hairs near mouth inside;

sepals oblong-linear, often keeled, 6–12 × 1–3 mm, abaxial surface densely pubescent;

petals bright pink to rose-purple, rarely white, broadly obcordate, 9–20 × 7–15 mm, apical notch 1–3 mm;

filaments white or pink, those of longer stamens 5–10 mm, those of shorter ones 2.5–6 mm;

anthers cream, 1.5–3 × 0.6–1.2 mm;

ovary 15–34 mm, densely villous and glandular puberulent;

style white or pink, 5–12 mm, usually glabrous, stigma deeply 4-lobed, 1.8–2.2 × 3–5.5 mm, lobes recurved or spreading, exserted beyond anthers.

erect;

buds 2–5 × 1–2.5 mm;

pedicel 2–14 mm;

floral tube 0.8–1 × 1.1–1.5 mm, conspicuous ring of spreading hairs at mouth inside, mixed strigillose and sparse glandular puberulent externally;

sepals lanceolate, somewhat keeled, 2.5–4 × 1–1.3 mm, abaxial surface strigillose;

petals rose-purple, 3.5–6 × 1.8–3 mm, apical notch 0.8–1.4 mm;

filaments pale pink, those of longer stamens 2–2.2 mm, those of shorter ones 0.8–1.3 mm;

anthers yellow, 0.7–0.8 × 0.4–0.5 mm;

ovary 12–38 mm, strigillose;

style white, 2.5–3.5 mm, glabrous, stigma clavate, 1.5–2 × 0.6–0.8 mm, surrounded by longer anthers.

Capsules

often flushed purple, 25–90 mm, surfaces usually densely villous and glandular puberulent, rarely glabrescent;

pedicel 5–20 mm.

40–70 mm, surfaces strigillose;

pedicel 4–16 mm.

Seeds

narrowly obovoid, 0.8–1.2 × 0.3–0.6 mm, chalazal collar inconspicuous, dark brown, surface coarsely papillose;

coma easily detached, tawny or dull white, 7–10 mm.

narrowly obovoid, 0.9–1 × 0.3–0.4 mm, chalazal collar inconspicuous, brown, surface coarsely papillose;

coma readily detached, dull white, 4–5 mm.

2n

= 36.

= 36.

Epilobium hirsutum

Epilobium obscurum

Phenology Flowering Jun–Sep. Flowering Jul–Aug.
Habitat Low wet areas along streams, rivers, ponds, and lakes, roadside ditches, along railroad tracks, marshes and swampy areas. Ruderal areas, banks of ditches, streams, edges of swampy areas.
Elevation 0–150[–3000] m. (0–500[–9800] ft.) 0–200[–500] m. (0–700[–1600] ft.)
Distribution
from FNA
CO; CT; IL; IN; KY; MA; MD; ME; MI; NH; NJ; NY; OH; OR; PA; RI; UT; VT; WA; WI; WV; BC; NB; NS; ON; PE; QC; Eurasia; Africa [Introduced in North America]
[WildflowerSearch map]
[BONAP county map]
from FNA
MI; WA; BC; Europe [Introduced in North America; introduced also in South America (Chile), Africa (Morocco), Pacific Islands (New Zealand), Australia (Tasmania)]
[BONAP county map]
Discussion

Epilobium hirsutum is very widespread in cool temperate Eurasia and montane regions, occurring throughout Europe except in the far north (P. H. Raven 1968), through the Caucasus and central Asia (E. I. Steinberg 1949) to Nepal (Raven 1962), China (Chen C. J. et al. 1992), and Japan (A. W. Lievens and P. C. Hoch 1999). It occurs as well along the Mediterranean coast of Africa, through East Africa to southern Africa, and in the Canary and Cape Verde Islands (Raven 1967).

Epilobium hirsutum exceeds almost all other species of the genus in stature, so its size, very large flowers, and densely villous aspect make it easy to identify. R. L. Stuckey (1970) provided a detailed account of the introduction and spread of E. hirsutum in North America, noting the earliest known collection (July 1829) was from Newport, Rhode Island. Most early collections appeared in waste areas, particularly near harbor ballast piles, although some may have been grown in gardens. By the 1890s this species was well established along the Atlantic coastal region from New Jersey and Philadelphia through New England, and around Niagara Falls in the Great Lakes region. During the twentieth century, E. hirsutum spread extensively in southern Ontario and Quebec, south along the Atlantic coast to Maryland, and to all of the states along the southern shores of the Great Lakes, most recently including Wisconsin (1970), and Indiana (1972). It occurs in much the same habitat as that of another, more widely publicized invader, Lythrum salicaria, and sometimes is recorded as a companion species. The earliest known collection in western North America was made in 1933 in Bingen (Klickitat County), Washington. Whether from that introduction or others, E. hirsutum is now naturalized and widespread in the Pacific Northwest. It also was reported recently from the Denver region in Colorado and near Midway in Utah.

Epilobium grandiflorum F. H. Wiggers and E. grandiflorum Allioni are illegitimate names that pertain here.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Epilobium obscurum, native throughout Europe and the European part of Russia except the far north, to Turkey and the Azores, is one of several Eurasian species that has naturalized in North America, following multiple early introductions around east coast port cities, and later around the Great Lakes. E. G. Voss(1972–1996, vol. 2) reported a collection of E. obscurum made in 1927 in Michigan near Detroit, but despite efforts by Voss and others, no additional collections of this species have been detected in that area, suggesting that it failed to become naturalized there.

In the Pacific Northwest, W. Suksdorf grew and collected at least six European taxa in his garden in Bingen (Klickitat County, Washington); this included E. obscurum (as early as 1922) but none of those taxa became naturalized. However, one or more independent new introductions in the Seattle (P. Zika, pers. comm.) and Vancouver (F. Lomer, pers. comm.) regions appear to be more persistent and the species should be considered naturalized there.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 10. FNA vol. 10.
Parent taxa Onagraceae > subfam. Onagroideae > tribe Epilobieae > Epilobium > sect. Epilobium Onagraceae > subfam. Onagroideae > tribe Epilobieae > Epilobium > sect. Epilobium
Sibling taxa
E. anagallidifolium, E. arcticum, E. brachycarpum, E. campestre, E. canum, E. ciliatum, E. clavatum, E. cleistogamum, E. coloratum, E. davuricum, E. densiflorum, E. densum, E. foliosum, E. glaberrimum, E. hallianum, E. hornemannii, E. howellii, E. lactiflorum, E. leptocarpum, E. leptophyllum, E. luteum, E. minutum, E. mirabile, E. montanum, E. nevadense, E. nivium, E. obcordatum, E. obscurum, E. oreganum, E. oregonense, E. pallidum, E. palustre, E. parviflorum, E. rigidum, E. saximontanum, E. septentrionale, E. siskiyouense, E. smithii, E. suffruticosum, E. torreyi
E. anagallidifolium, E. arcticum, E. brachycarpum, E. campestre, E. canum, E. ciliatum, E. clavatum, E. cleistogamum, E. coloratum, E. davuricum, E. densiflorum, E. densum, E. foliosum, E. glaberrimum, E. hallianum, E. hirsutum, E. hornemannii, E. howellii, E. lactiflorum, E. leptocarpum, E. leptophyllum, E. luteum, E. minutum, E. mirabile, E. montanum, E. nevadense, E. nivium, E. obcordatum, E. oreganum, E. oregonense, E. pallidum, E. palustre, E. parviflorum, E. rigidum, E. saximontanum, E. septentrionale, E. siskiyouense, E. smithii, E. suffruticosum, E. torreyi
Synonyms Chamaenerion hirsutum, E. amplexicaule, E. aquaticum, E. hirsutum var. villosum, E. villosum
Name authority Linnaeus: Sp. Pl. 1: 347. (1753) Schreber: Spic. Fl. Lips., 147, [155]. (1771)
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