Epilobium hirsutum
Epilobium obcordatum
codlins-and-cream, fiddle grass, fiddle grass willowherb, great or great hairy willowherb, great willowherb, hairy willlowherb, hairy willow-herb, épilobe hirsute
heart willowweed, rock fringe, rockfringe willowherb, rose willowherb
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.
many, decumbent to ascending, clumped or cespitose, green to grayish green, terete, 5–15 cm, branched mainly proximally, subglabrous and ± glaucous proximal to inflorescence, ± canescent distally or throughout.
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, usually crowded and exceeding internodes, subsessile or petiole 1–2 mm;
blade green or grayish green, usually broadly lanceolate-elliptic to ovate or obovate, rarely suborbiculate, 0.6–2.4 × 0.4–1.3(–1.9) cm, base rounded to subcordate, margins low denticulate, 4–9 teeth per side, veins indistinct, 4–7 per side, apex obtuse proximally to acute distally, surfaces usually subglabrous, rarely canescent, especially on margins and veins;
bracts much reduced.
erect racemes or panicles, usually densely villous and glandular puberulent, rarely tomentose.
ascending to erect, sparse racemes or loose panicles, ± densely canescent and glandular puberulent.
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 7–13 × 3–5 mm, apex acute, sometimes with stigma exserted;
pedicel 3–10 mm;
floral tube 3.2–5.5 × 2.2–4.2 mm, slightly raised ring of spreading hairs0.4–1 mm from base inside;
sepals (5–)8.5–14 ×1.8–2.9 mm;
petals pink to rose-purple, obcordate, (12–)15–26 × (7–)9–14.6 mm, apical notch 2.5–7.2 mm;
filaments cream to pink, those of longer stamens 8.5–16 mm, those of shorter ones 5.5–11 mm;
anthers cream-yellow, 1.6–2.9 × 0.6–1.3 mm;
ovary 9–22 mm, usually canescent and glandular puberulent, rarely subglabrous;
style cream to light pink, 11–23 mm, glabrous, stigma deeply 4-lobed, 1–1.5 × 2.2–4.5 mm, exserted beyond anthers.
often flushed purple, 25–90 mm, surfaces usually densely villous and glandular puberulent, rarely glabrescent;
pedicel 5–20 mm.
straight, subclavate, 16–40 mm, surfaces canescent and glandular puberulent;
pedicel 5–15 mm.
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, 1.4–2.1 × 0.6–0.9 mm, with low chalazal collar 0.4–0.5 mm wide, light or grayish brown, surface papillose;
coma easily detached, tawny, 5–9 mm.
= 36.
= 36.
Epilobium hirsutum
Epilobium obcordatum
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 obcordatum is an uncommon but relatively widespread and very characteristic species of the high Sierra Nevada, extending to scattered high ranges in northeastern Nevada, Idaho, and southeastern Oregon (Steens Mountains). Its low, clumped habit, dense green and often glaucous foliage, and large flowers make it one of the more attractive species of the genus, with considerable potential as a cultivated plant in rock gardens. Although it bears some general morphological similarities with two species in western North America, E. rigidum and E. siskiyouense, as discussed under those taxa, E. obcordatum also bears close resemblance to E. nankotaizanense Yamamoto, an alpine endemic from Taiwan, China (Chen C. J. et al. 1992). It is uncertain whether they are actually related or have evolved similar morphologies independently in similar high montane habitats on either side of the north Pacific.
Little has been reported on the pollination biology of Epilobium obcordatum, but its large flowers with marked protandry and herkogamy strongly suggest that the plants are outcrossing, probably pollinated by large bees.
Epilobium obcordatum shows considerable morphological variation, especially in leaf shape (ranging from narrowly ovate to orbiculate) and pubescence pattern. In the latter, plants mainly in the Sierra Nevada have stems glabrous and often glaucous below the inflorescence and mixed canescent and glandular puberulent distally. Plants mainly in Idaho and Nevada have stems sparsely to moderately canescent and inflorescences densely mixed canescent and glandular puberulent. But some collections, including the type of E. obcordatum var. puberulum, are mixed, and these pubescence differences do not correlate with other morphological or eco-geographical characters.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
BC
OR
WA
Flora NW
Go Botany
IL Wildflowers
MD Biodiversity
MI Flora
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
CA
