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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

Oregon willowherb, slim-stem willowweed

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 slender stolons to 18 cm with minute, rounded leaves.
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, often loosely matted, often flushed purple distally, terete, 8–30(–40) cm, simple or sparsely branched from base, subglabrous.

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, subsessile;

blade broadly elliptic proximally, narrowly elliptic or lanceolate to sublinear distally, 5–25 × 1–7 mm, longer than internodes proximally to much shorter distally, base cuneate to rounded, margins subentire, veins extremely faint, 3–5 per side, apex obtuse, surfaces subglabrous;

bracts extremely reduced and linear.

Inflorescences

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

usually erect, sometimes nodding in bud, racemes, open, unbranched, sparsely strigillose and glandular puberulent.

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.

suberect or nodding;

buds 2–3.5 × 1–1.5 mm, apex blunt;

pedicel 2–7 mm;

floral tube 0.8–1.8 × 1–2.1 mm, with faint ring of hairs at mouth inside;

sepals often flushed purple, 2.5–4.5 × 1–1.6 mm;

petals white to pink, 5–8 × 2.8–4 mm, apical notch 0.8–1.5 mm;

filaments white, those of longer stamens 2.8–4.5 mm, those of shorter ones 2–3.8 mm;

anthers yellow-cream, 0.8–1.2 × 0.4–0.5 mm;

ovary green to purple, 8–14 mm, sparsely strigillose and glandular puberulent;

style white, 3.8–4.8 mm, glabrous, stigma subcapitate, 1–1.4 × 1–1.2 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.

slender, often purplish green, 21–40(–52) mm, surfaces subglabrous;

pedicel 20–65 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.

narrowlyoblanceoloid or subfusiform, 1–1.4 × 0.4–0.6 mm, chalazal collar 0.1–0.2 mm, light brown, surface low papillose;

coma persistent, whitish, 3–4 mm.

2n

= 36.

= 36.

Epilobium hirsutum

Epilobium oregonense

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. Montane to subalpine boggy or mossy areas, wet meadows, protected, semi-shaded stream banks.
Elevation 0–150[–3000] m. (0–500[–9800] ft.) 1200–3000(–3500) m. (3900–9800(–11500) 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
AZ; CA; CO; ID; MT; NM; NV; OR; UT; WA; WY; BC
[WildflowerSearch map]
[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 oregonense is a distinctive western North American endemic, found primarily throughout the Cascade–Sierra mountain complex barely into the Transverse Ranges of southern California, and very scattered through the Rocky Mountains. It is exceedingly rare in Arizona, Colorado, and New Mexico.

Even though Epilobium oregonense bears some similarity to E. anagallidifolium and other members of the Alpinae group, and often grows in close proximity to them, this species does not share the derived CC chromosomal arrangement with that group, instead having the more globally widespread BB arrangement. The similarities with E. anagallidifolium include the small stature, small, obtuse, and subentire leaves, and long pedicels in fruit; however, E. oregonense differs by its long, threadlike stolons, distal leaves extremely narrow and reduced in size relative to the internodes, and near complete absence of pubescence on the plant, including a lack of raised lines of hairs on the stems.

Another species with which Epilobium oregonense has been confused is E. hallianum, but that species always forms condensed basal turions, is more strictly erect, and generally has larger and more denticulate leaves. The distinctive and diagnostic stolons of E. oregonense are similar to those found in E. palustre and related species (all of which also have the BB chromosome arrangement), except that those of E. oregonense never terminate in a condensed turion, as found in those other species. The exact affinities of E. oregonense remain uncertain, but it appears to be most closely related to the E. palustre complex.

Some specimens of Epilobium oregonense grow as floating mats in cold streams; these specimens are notably large, with particularly strong development of basal stolons and larger, more lanceolate leaves. As evidenced by mixed herbarium collections, E. oregonense grows sympatrically with several congeners, including E. anagallidifolium, E. ciliatum subspp. ciliatum and glandulosum, E. hallianum, and E. hornemannii, and hybridizes occasionally, at least with E. ciliatum subsp. ciliatum and E. hornemannii.

Epilobium oregonense var. gracillimum Trelease, which pertains here, was not validly published, and other names based on it are also invalid.

(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. obscurum, E. oreganum, 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) Haussknecht: Monogr. Epilobium, 276, plate 14, fig. 66. (1884)
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