Euphorbia marginata

Pursh

Fl. Amer. Sept. 2: 607. 1813.

Common names: Snow-on-the-mountain euphorbe marginée
WeedyIllustrated
Synonyms: Euphorbia bonplandii Sweet Lepadena marginata (Pursh) Nieuwland
Treatment appears in FNA Volume 12. Treatment on page 248. Mentioned on page 238, 241, 243.

Herbs, annual, with taproot. Stems erect, unbranched or branched, 30–85 (–150) cm, pilose or glabrous. Leaves alternate; stipules 0.1–0.3 mm; petiole 0.2–3 mm, glabrous or minutely pilose; blade broadly ovate to elliptic, 32–62 (–82) × 18–28 (–52) mm, base rounded to cuneate, margins entire, often white on distal leaves, apex acute, rarely mucronate, surfaces glabrous; venation obscure, only midvein conspicuous. Cyathia in terminal pleiochasia, dichasial bracts narrowly elliptic to oblanceolate with conspicuous white margins; peduncle 1.8–2.7 (–22) mm, densely pilose. Involucre campanulate, 2.2–3.5 × 1.3–2.3 mm, margin between glands deeply divided into fringe of fimbriate lobes, pilose; glands 4–5, green to greenish yellow, reniform to subcircular, 0.7–1.1 × 1–1.6 mm; appendages white, orbiculate, 1.5–2.7 × 1.9–2.9 (–3.6) mm, entire. Staminate flowers 30–70. Pistillate flowers: ovary pilose; styles 1–2.5 mm, 2-fid 1/2–2/3 length. Capsules oblate, 3–5 × 3.5–7.5 mm, moderately to densely pilose; columella 3–4.1 mm. Seeds orange-tan to gray, ovoid, 3.7–3.9 × 3–3.3 mm, rugose, with 2 transverse ridges (one dark orange to brown, other inconspicuous); caruncle absent. 2n = 56.


Phenology: Flowering and fruiting summer–fall.
Habitat: Disturbed areas and grasslands.
Elevation: 0–1700 m.

Distribution

V12 377-distribution-map.jpg

Man., Ont., Que., Sask., Ark., Calif., Colo., Conn., Ill., Ind., Iowa, Kans., La., Md., Mass., Mich., Minn., Mo., Mont., Nebr., N.H., N.Mex., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Va., W.Va., Wis., Wyo., c, s Mexico

Discussion

Euphorbia marginata is native to the central United States. The type specimen was collected by Meriwether Lewis along the Yellowstone River in southern Montana in 1806, and it has been reported to be native as far south as Arizona, New Mexico, and Texas, and as far east as southern Minnesota, western Iowa, and Missouri (G. Yatskievych 1999–2013, vol. 2). It is presumably naturalized outside of this area. Euphorbia marginata is widely cultivated as an ornamental for its showy, white-margined distal leaves, and it can escape locally.

Selected References

None.

Lower Taxa

None.

"connate" is not a number. "distinct" is not a number."/2" is not declared as a valid unit of measurement for this property. "/3" is not declared as a valid unit of measurement for this property.

... more about "Euphorbia marginata"
mucronate;acute +
0.29 cm2.9 mm <br />0.0029 m <br /> (0.36 cm3.6 mm <br />0.0036 m <br />) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.27 cm2.7 mm <br />0.0027 m <br />) +
orbiculate +
0.19 cm1.9 mm <br />0.0019 m <br /> (0.29 cm2.9 mm <br />0.0029 m <br />) +
Jess A. Peirson +, Victor W. Steinmann +  and Jeffery J. Morawetz +
rounded +  and cuneate +
Alectoroctonum +
6.2 cm62 mm <br />0.062 m <br /> (8.2 cm82 mm <br />0.082 m <br />) +
2.8 cm28 mm <br />0.028 m <br /> (5.2 cm52 mm <br />0.052 m <br />) +
3.2 cm32 mm <br />0.032 m <br /> (6.2 cm62 mm <br />0.062 m <br />) +
broadly ovate;elliptic +
1.8 cm18 mm <br />0.018 m <br /> (2.8 cm28 mm <br />0.028 m <br />) +
whorled +  and not opposite +
narrowly elliptic +  and oblanceolate +
cymose +, few-branched +  and unbranched +
additional +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.75 cm7.5 mm <br />0.0075 m <br />) +
exfoliating +
ceraceous +
0.3 cm3 mm <br />0.003 m <br /> (0.41 cm4.1 mm <br />0.0041 m <br />) +
Snow-on-the-mountain +  and euphorbe marginée +
Man. +, Ont. +, Que. +, Sask. +, Ark. +, Calif. +, Colo. +, Conn. +, Ill. +, Ind. +, Iowa +, Kans. +, La. +, Md. +, Mass. +, Mich. +, Minn. +, Mo. +, Mont. +, Nebr. +, N.H. +, N.Mex. +, N.Y. +, N.C. +, Ohio +, Okla. +, Pa. +, R.I. +, S.C. +, S.Dak. +, Tenn. +, Tex. +, Utah +, Va. +, W.Va. +, Wis. +, Wyo. +, c +  and s Mexico +
0–1700 m. +
pistillate +  and staminate +
green +  and greenish yellow +
0.7mm;1.1mm +
subtending +
4 +  and 5 +
reniform +  and subcircular +
1mm +  and 1.6mm +
Disturbed areas and grasslands. +
pleiochasial +  and dichasial +
axillary +  and terminal +
0.22 cm2.2 mm <br />0.0022 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
campanulate +
0.13 cm1.3 mm <br />0.0013 m <br /> (0.23 cm2.3 mm <br />0.0023 m <br />) +
caducous +, deciduous +  and persistent +
bractlike +
fimbriate +
palmate +  and pinnate +
conspicuous +
crenulate +
0.27 cm2.7 mm <br />0.0027 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.27 cm2.7 mm <br />0.0027 m <br />) +
connate;distinct +
pilose +  and glabrous +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
Flowering and fruiting summer–fall. +
opposite +  and whorled +
with white margins +  and green +
Fl. Amer. Sept. +
orange-tan;gray +
0.37 cm3.7 mm <br />0.0037 m <br /> (0.39 cm3.9 mm <br />0.0039 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.33 cm3.3 mm <br />0.0033 m <br />) +
Weedy +  and Illustrated +
free +, connate +  and distinct +
branched +  and unbranched +
85 cm850 mm <br />0.85 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
prostrate +  and decumbent +
glabrous +  and pilose +
30 cm300 mm <br />0.3 m <br /> (85 cm850 mm <br />0.85 m <br />) +
deciduous +  and persistent +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (?) +  and 0.25 cm2.5 mm <br />0.0025 m <br /> (?) +
Euphorbia bonplandii +  and Lepadena marginata +
Euphorbia marginata +
Euphorbia sect. Alectoroctonum +
species +
in terminal monochasia +  and solitary +
10 +, 9 +, 8 +, 7 +  and 6 +