Euthamia leptocephala |
Euthamia |
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goldentop |
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Habit | Herbs or subshrubs perennial; rhizomatous. | |
Stems | usually 1; erect; branches few to many, sometimes woody proximally; leafy throughout, glabrous. |
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Leaves | cauline, alternate, slightly reduced distally, sometimes with tufts of linear leaves on short axillary branches; blades narrowly elliptic-lanceolate to linear; margins entire; veins 3–5; parallel from bases; tips acute or acuminate; surfaces glabrous; ± glandular-punctate, sessile. |
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Inflorescences | numerous small heads clustered on branch tips in panicle-like arrays, sometimes ± flat-topped. |
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Involucres | cylindrical or narrowly campanulate. |
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Receptacles | convex; paleae 0. |
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Ray florets | pistillate; rays exceeding involucres, yellow. |
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Disc florets | bisexual; corollas cylindric, widened in distal half, yellow; lobes 5, narrowly triangular, spreading to recurved at anthesis; stamens 5; well exserted from corollas; stigmas exserted from stamen tubes. |
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Phyllaries | in 4–6 unequal series; erect, spreading in fruit, narrowly lanceolate or linear; outer gradually shorter; colorless or green-tipped; outermost often green throughout; midribs indistinct; surfaces glabrous, resinous. |
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Fruits | cylindrical, truncate, tapering to bases, inconspicuously ribbed, pappi of numerous fine bristles. |
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Heads | radiate. |
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Euthamia leptocephala |
Euthamia |
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Distribution | ||
Discussion | Asia, Europe, North America. 5 species; 1 species treated in Flora. Euthamia graminifolia has been recorded in Oregon as an adventive species in cranberry bogs in Curry County. Its native range is to the north and east of Oregon, extending from Washington through Canada, to the central and eastern United States. The specimens collected in Oregon resemble E. graminifolia in the shape of their inflorescences and involucral phyllaries. However, the specimens do not have the kind of robust growth needed in order to rule out environmental variation in E. occidentalis as the source of these traits. |
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Source | Flora of Oregon, volume 2, page 270 Kenton Chambers |
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Sibling taxa | ||
Subordinate taxa | ||
Web links |