OregonFlora: Euthamia graminifolia vs. Euthamia occidentalis

	Euthamia graminifolia	Euthamia occidentalis
	flat-top goldentop	western goldenrod, western goldentop
Habit		Plants 4–20 dm.
Leaves		4–12 cm; gland-dotted.
Involucres		3.5–5 mm.
Ray florets		15–25, inconspicuous; rays 2–2.5 mm.
Disc florets		8–15; corollas 3–4 mm, equaling involucres.
Phyllaries		outer tips obtuse to acute; inner tips acute to acuminate.
Fruits		0.75–1 mm, pale brown, strigose; pappus bristles 3–4 mm, white.
2n		=18.

	Euthamia graminifolia	Euthamia occidentalis
Distribution	[WildflowerSearch map] [BONAP county map]	[WildflowerSearch map] [BONAP county map]
Discussion		Moist flats, slopes, open woods, riverbanks, fresh or saline marshes, roadside ditches, deflation plains. Flowering Jul–Oct. 0–1600 m. All ecoregions except Casc. CA, ID, NV, WA; north to British Columbia, northeast to MT, east to NE, southeast NM, south to Mexico. Native. Euthamia occidentalis is best distinguished from the related E. graminifolia by its overall more elongate inflorescence, the proximal branches being shorter than the distal ones, and not forming a mostly flat-topped unit as in the latter species. However, on less robust individuals having only a few clusters of heads, this difference may not be so clear.
Source		Flora of Oregon, volume 2, page 270 Kenton Chambers
Sibling taxa	E. occidentalis	E. graminifolia
Synonyms		Solidago occidentalis
Web links	Local floras: BC, OR, WA Local Web sites: Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria, Turner Photog. WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Euthamia occidentalis

flat-top goldentop

western goldenrod, western goldentop

Habit

Plants 4–20 dm.

Leaves

4–12 cm;

gland-dotted.

Involucres

3.5–5 mm.

Ray florets

15–25, inconspicuous;

rays 2–2.5 mm.

Disc florets

8–15;

corollas 3–4 mm, equaling involucres.

Phyllaries

outer tips obtuse to acute; inner tips acute to acuminate.

Fruits

0.75–1 mm, pale brown, strigose;

pappus bristles 3–4 mm, white.

=18.

Euthamia occidentalis

Distribution

[WildflowerSearch map]

[BONAP county map]

[WildflowerSearch map]

[BONAP county map]

Discussion

Moist flats, slopes, open woods, riverbanks, fresh or saline marshes, roadside ditches, deflation plains. Flowering Jul–Oct. 0–1600 m. All ecoregions except Casc. CA, ID, NV, WA; north to British Columbia, northeast to MT, east to NE, southeast NM, south to Mexico. Native.

Euthamia occidentalis is best distinguished from the related E. graminifolia by its overall more elongate inflorescence, the proximal branches being shorter than the distal ones, and not forming a mostly flat-topped unit as in the latter species. However, on less robust individuals having only a few clusters of heads, this difference may not be so clear.

Source

Flora of Oregon, volume 2, page 270
Kenton Chambers

Sibling taxa

E. occidentalis

E. graminifolia

Synonyms

Solidago occidentalis

Web links