Duration: Annual
Nativity: Native
Lifeform: Forb/Herb
General: Herbaceous annuals, to 1.5 m tall, stems erect, herbage glabrous or hairy and becoming glabrous with age.
Leaves: Alternate, linear, 2-7 cm long, tip acute to obtuse and abruptly pointed, margins entire, surfaces hairy, becoming glabrous, blades short-petiolate with minute, obscure stipules.
Flowers: Staminate and pistillate; involucres obconic 1.5-2 mm long with pubescent surfaces, hairs white, staminate flowers 23-36, generally in 5 clusters around the solitary, central pistillate flower, pistillate flowers stalked with 3 ovary chambers with 1 ovule 1 per chamber, styles red, 3 and undivided, infloresences with 5 fused bracts and 4-5 glands alternating with bracts, the glands concealed by 5-7 strigose inflexed segments, flowers borne solitary or with a few flowers clustered at branch tips, with 1-3 round, cupped glands to 1.5 mm long, with 5-7 lobes curving over the glands.
Fruits: Oblong, 3-lobed (the lobes obscure) capsules 4-5 mm long, plainly longer than wide, with hairy surfaces. Seeds white to gray, 3.5-4 mm long, flattened top to bottom, 4-angled with tubercled surfaces and an obvious caruncle with a stipitate surface.
Ecology: Found on dry soils on hot, rocky slopes and in canyons, from 300-3,500 ft (91-1067 m); flowering February-October.
Distribution: Arizona, California, New Mexico, Texas.
Notes: The thin, linear leaves stand out at right angles to the stems, sometimes becoming reddish or purplish with age and the stalked fruits are relatively large when compared to the rest of the plant. Kearney and Peebles give the keys to this species as the scacely lobed capsules plainly longer than wide, the seeds markedly wider than thick with an obvious, stipitate (spotted) caruncle, and the floral glands concealed by 5-7 inflexed, strigose segments. Look for this species in Arizona in Graham, Maricopa, Pinal, Pima, and Yuma counties.
Etymology: Euphorbia is named for Euphorbus, Greek physician of Juba II, King of Mauretania, and eriantha means woolly-flowered.
Synonyms: None
Editor: LCrumbacher2012
