Euphorbia oblongata |
Euphorbia melanadenia |
|
---|---|---|
Balkan spurge, egg-leaf spurge, oblong spurge |
red-gland spurge, squaw sandmat |
|
Habit | Herbs, perennial, with woody taproot. | Herbs, perennial, with moderately to strongly thickened rootstock. |
Stems | erect, unbranched or densely branching, 80 cm, often densely villous (especially young stems and pleiochasial branches). |
ascending to erect, 5–20 cm, sericeous to appressed-villous. |
Leaves | petiole absent; blade oblong to narrowly obovate or lanceolate, 15–70 × 6–25 mm, base rounded or truncate, margins finely serrulate, apex obtuse, mucronulate, surfaces glabrous; venation inconspicuously pinnate, midvein prominent. |
opposite; stipules distinct (lower side) and connate (upper side), linear, 0.5–1 mm, densely pilose; petiole 0.8–1.5 mm, tomentose; blade ovate, 1.2–5 × 0.8–2.9 mm, base asymmetric, hemicordate, margins entire, apex rounded to acute, surfaces tomentose; venation inconspicuous. |
Involucre | cupulate to slightly turbinate, 1.5–2.5 × 1.3–1.5 mm, glabrous; glands 2–3, elliptic, 0.6–0.8 × 0.8–1.2 mm; horns absent. |
campanulate, 0.6–1.1 × 0.7–1 mm, tomentose; glands 4, deep red to purple, elliptic, 0.3–0.4 × 0.4–0.7 mm; appendages white or becoming pink with age, oblong to flabellate, 0.4–0.7(–1) × 0.7–1.2 mm, distal margin entire or erose. |
Staminate flowers | 15–40. |
45–80. |
Pistillate flowers | ovary glabrous; styles 1.5–2 mm, 2-fid. |
ovary tomentose, styles 0.5–0.8 mm, 2-fid nearly entire length. |
Capsules | globose, 3–4.5 × 3–4.5 mm, slightly 3-lobed; cocci rounded, verrucose-tuberculate, glabrous; columella 2.5–3.3 mm. |
ovoid, 1.4–1.8 × 1.4–1.7 mm, tomentose; columella 1.2–1.5 mm. |
Seeds | brown, ovoid, 2.4–2.6 × 1.3–2 mm, smooth, caruncle reniform, 0.2–0.3 × 0.8–0.9 mm. |
gray to tan, oblong, 4-angled in cross section, 1–1.2 × 0.4–0.6 mm, smooth to wrinkled or alveolate. |
Cyathial | arrangement: terminal pleiochasial branches 3–5, each 2–3 times 2–4-branched; pleiochasial bracts ovate, similar in size to distal leaves; dichasial bracts distinct, ovate to suborbiculate, base truncate or rounded, margins entire or finely denticulate, apex obtuse, sometimes mucronulate; axillary cymose branches 0–4. |
|
Cyathia | peduncle 1–5 mm. |
solitary at distal nodes; peduncle (0.6–)1.4–1.9 mm. |
Euphorbia oblongata |
Euphorbia melanadenia |
|
Phenology | Flowering and fruiting spring–fall. | Flowering and fruiting year-round. |
Habitat | Waste areas, disturbed sites, roadsides, fields, pastures. | Rocky slopes, river washes, dry to wet soils. |
Elevation | 30–900 m. (100–3000 ft.) | 400–1400 m. (1300–4600 ft.) |
Distribution |
CA; OR; WA; s Europe [Introduced in North America]
|
AZ; CA; Mexico (Baja California, Sonora)
|
Discussion | Euphorbia oblongata is listed as a noxious weed by the states of California, Oregon, and Washington. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Euphorbia melanadenia is similar in appearance to E. cinerascens, but E. melanadenia has conspicuous involucral gland appendages whereas E. cinerascens has inconspicuous appendages or lacks them entirely. Euphorbia melanadenia occurs in Arizona and southern California, whereas E. cinerascens is found only in southern and western Texas. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 305. | FNA vol. 12, p. 276. |
Parent taxa | Euphorbiaceae > Euphorbia > subg. Esula | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Tithymalus oblongatus | Chamaesyce melanadenia |
Name authority | Grisebach: Spic. Fl. Rumel. 1: 136. (1843) | Torrey: in War Department [U.S.], Pacif. Railr. Rep. 4(5): 135. (1857) |
Web links |
|