Helenium thurberi A. Gray
Family: Asteraceae
Thurber's sneezeweed
Helenium thurberi image
Liz Makings  
Annuals, 40-100 cm. Stems usually 1, branched distally, moderately winged, sparsely hairy proximally, moderately hairy distally. Leaves glabrous or sparsely hairy (basal leaves withered by flowering); proximal blades lanceolate to lance-linear, usually irregularly laciniate; mid and distal blades lance-linear, entire. Heads 10-75(-120+) per plant, in paniculiform arrays. Peduncles 3-10 cm, moderately hairy. Involucres ovoid to conic, 6-10 × 5-10 mm. Phyllaries (strongly connate proximally), moderately hairy. Ray florets 0. Disc florets 225-500+; corollas yellow-green proximally, brown to reddish brown distally, 1-1.3 mm, lobes 4. Cypselae 0.9-1.2(-1.5) mm, moderately hairy; pappi of 6(-7) entire, non-aristate scales 0.2-0.5 mm. 2n = 26. Flowering (Mar-)May-Jul(-Sep). Ditches, around ponds, along streams, moist fields; 30-1600 m; Ariz.; Mexico.
Wiggins 1964, FNA 2006, Kearney and Peebles 1969
Duration: Annual Nativity: Native Lifeform: Forb/Herb General: Ascending, much branched annual 40-100 cm tall, stems slender, puberulent, obviously winged, sparsely hairy near the base, moderately hairy above. Leaves: Lower oblanceolate, 5-15 cm long, more or less puberulent, subentire to sharply dentate, upper leaves lanceolate to lance-linear, 2-7 cm long, entire. Flowers: Heads on slender peduncles 3-10 cm long, striate, heads 10-75 per plant, in paniculiform arrays, discoid, broadly ovoid to subglobose, 5-12 mm in diameter with linear involucral bracts 3-7 mm long, slightly hirsutulous, corollas greenish yellow, faintly tinged with purplish or brownish at tips of lobes, about 1 mm long; no ray florets, 225-500+ disc florets. Fruits: Cypselae about 1 mm long moderately hairy with pappi of 6 entire, non-aristate scales. Ecology: Found in marshy places along streams, in moist disturbed sites from 100-5,500 ft (31-1676 m); flowers April-October. Distribution: s AZ; south to c MEX. Notes: Distinguished by the winged stems and heads with lack of rays and many, many disc florets. Ethnobotany: Unknown Etymology: Helenium is thought to be named for Helen of Troy by Linnaeus, while thurberi is named for Dr. George Thurber (1821-1890) a botanist on the Mexican Boundary Survey of 1850-1854. Synonyms: None Editor: SBuckley 2010, FSCoburn 2015
Helenium thurberi image
Sue Carnahan  
Helenium thurberi image
Sue Carnahan  
Helenium thurberi image
Sue Carnahan  
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image
Helenium thurberi image