OregonFlora: Cotula coronopifolia

	Cotula coronopifolia
	brass buttons
Habit	Plants perennial, 5–45 cm; usually stoloniferous.
Stems	decumbent to erect; simple to well branched, glabrous or minutely glandular.
Leaves	linear to linear-lanceolate, 1–7 cm, bases auriculate and forming a membranous sheath around stem; margins entire or few-lobed; lobes linear; tips acute; surfaces glabrous, sometimes gland-dotted, sessile.
Peduncles	1–9 cm.
Involucres	hemispheric, 3–4 mm.
Disc florets	corollas 1–1.5 mm, equaling or exceeding involucres, yellow.
Phyllaries	3–5-veined; surfaces glabrous; inner obtuse; outer obtuse or acute.
Fruits	0.7–1.8 mm, glabrous or minutely glandular, brown, winged or not.
2n	=20.

	Cotula coronopifolia
Distribution	[WildflowerSearch map] [BONAP county map]
Discussion	Beaches, tide marshes, moist fields, disturbed areas. Flowering Mar–Dec. 0–200 m. Est. CA, NV, WA; north to British Columbia, southeast to AZ, south to Mexico; Africa, Australia, Europe, South America. Exotic.
Source	Flora of Oregon, volume 2, page 234 Kenton Chambers
Sibling taxa	C. australis, C. mexicana
Web links	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

Cotula coronopifolia

brass buttons

Habit

Plants perennial, 5–45 cm; usually stoloniferous.

Stems

decumbent to erect; simple to well branched, glabrous or minutely glandular.

Leaves

linear to linear-lanceolate, 1–7 cm, bases auriculate and forming a membranous sheath around stem;

margins entire or few-lobed;

lobes linear;

tips acute;

surfaces glabrous, sometimes gland-dotted, sessile.

Peduncles

1–9 cm.

Involucres

hemispheric, 3–4 mm.

Disc florets

corollas 1–1.5 mm, equaling or exceeding involucres, yellow.

Phyllaries

3–5-veined;

surfaces glabrous; inner obtuse; outer obtuse or acute.

Fruits

0.7–1.8 mm, glabrous or minutely glandular, brown, winged or not.

=20.

Cotula coronopifolia

Distribution

[WildflowerSearch map]

[BONAP county map]

Discussion

Beaches, tide marshes, moist fields, disturbed areas. Flowering Mar–Dec. 0–200 m. Est. CA, NV, WA; north to British Columbia, southeast to AZ, south to Mexico; Africa, Australia, Europe, South America. Exotic.

Source

Flora of Oregon, volume 2, page 234
Kenton Chambers

Sibling taxa

C. australis, C. mexicana

Web links