OregonFlora: Euphorbia myrsinites

	Euphorbia myrsinites
	myrtle spurge
Habit	Herbs perennial, 1–4 dm; stems decumbent to ascending, glabrous.
Leaves	alternate (upper and floral leaves may be opposite or whorled), densely crowded on stem, obovate to obovate-oblong, 10–45 × 5–16 mm; margins entire to serrulate at least in upper 25%; tips mucronate; surfaces glabrous, glaucous;
Inflorescences	involucres cone- to bell-shaped, 1.5–3 mm; glands shortly 2-horned.
Fruits	round to oblong, 5–7mm.
Seeds	round to oblong, 3–4 mm; smooth or wrinkled.
±	sessile.

	Euphorbia myrsinites
Distribution	[WildflowerSearch map] [BONAP county map]
Discussion	Disturbed areas, escaped from nearby cultivation. Flowering Apr–Jun. 500–1000 m. BW, Col, Lava. CA, ID, WA; scattered in western US, MI, Ontario; Europe. Exotic. The densely crowded leaves on the stems and decumbent to ascending habit easily distinguish E. myrsinites from all other members of this genus in Oregon.
Source	Flora of Oregon, volume 2, page 645 Stephen Meyers
Sibling taxa	E. crenulata, E. cyparissias, E. dentata, E. esula, E. helioscopia, E. lathyris, E. oblongata, E. peplus, E. spathulata
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, 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

Euphorbia myrsinites

myrtle spurge

Habit

Herbs perennial, 1–4 dm; stems decumbent to ascending, glabrous.

Leaves

alternate (upper and floral leaves may be opposite or whorled), densely crowded on stem, obovate to obovate-oblong, 10–45 × 5–16 mm;

margins entire to serrulate at least in upper 25%;

tips mucronate;

surfaces glabrous, glaucous;

Inflorescences

involucres cone- to bell-shaped, 1.5–3 mm;

glands shortly 2-horned.

Fruits

round to oblong, 5–7mm.

Seeds

round to oblong, 3–4 mm; smooth or wrinkled.

sessile.

Euphorbia myrsinites

Distribution

[WildflowerSearch map]

[BONAP county map]

Discussion

Disturbed areas, escaped from nearby cultivation. Flowering Apr–Jun. 500–1000 m. BW, Col, Lava. CA, ID, WA; scattered in western US, MI, Ontario; Europe. Exotic.

The densely crowded leaves on the stems and decumbent to ascending habit easily distinguish E. myrsinites from all other members of this genus in Oregon.

Source

Flora of Oregon, volume 2, page 645
Stephen Meyers

Sibling taxa