Helianthus radula (Pursh) Torr. & A.Gray

Rayless sunflower (en)

Species

Angiosperms > Asterales > Asteraceae > Helianthus

Characteristics

Perennials, 50–100 cm (with crown buds). Stems erect, distally densely hispid. Leaves mostly basal; opposite; petioles obscure (intergrading with blades); blades obovate to orbiculate, 4.6–14.5 × 2.1–12 cm, bases broadly cuneate to rounded, margins entire or serrulate, abaxial faces strigoso-hispid, not gland-dotted (cauline usually much smaller, alternate distally). Heads usually borne singly. Peduncles 10–20 cm. Involucres shallowly hemispheric, (15–25 ×) 5–8 mm. Phyllaries (often dark purple) 25–33, lanceolate to ovate, 10–14 × 3–5 mm, apices acute to acuminate, abaxial faces hispid or glabrous. Paleae 9–10 mm, subentire to 3-toothed (apices purplish, mucronate). Ray florets 0 or 2–8; laminae (sometimes purplish) 1–2(–10) mm. Disc florets 100–150+; corollas 7–8 mm, lobes reddish; anthers dark, appendages dark. Cypselae 3–4 mm, glabrate; pappi of 2 (often unequal) aristate scales 0.5–2.9 mm. 2n = 34.
Life form perennial
Growth form herb
Growth support free-standing
Foliage retention deciduous
Sexuality hermaphrodite
Pollination -
Spread -
Mature width (meter) -
Mature height (meter) 0.5 - 1.0
Root system -
Rooting depth (meter) -
Root diameter (meter) 0.6
Flower color
Blooming months
JanFebMar
AprMayJun
JulAugSep
OctNovDec
Fruit color -
Fruiting months -
Nitrogen fixer -
Photosynthetic pathway -

Environment

Light 7-9
Soil humidity 3-7
Soil texture -
Soil acidity -
Soil nutriment -
Hardiness (USDA) 4-10

Usage

Uses gene source
Edible -
Therapeutic use -
Human toxicity -
Animal toxicity -

Cultivation

Mode -
Germination duration (days) 10 - 14
Germination temperacture (C°) -
Germination luminosity -
Germination treatment -
Minimum temperature (C°) -
Optimum temperature (C°) -
Size -
Vigor -
Productivity -

Distribution

Helianthus radula world distribution map, present in United States of America

Identifiers

LSID urn:lsid:ipni.org:names:1074141-2
WFO ID wfo-0000045849
COL ID 3K5ZW
BDTFX ID -
INPN ID -
Wikipedia (EN) Link
Wikipedia (FR)

Synonyms

Rudbeckia radula Rudbeckia apetala Helianthus radula Centrocarpha radula Helianthus apetalus Echinomeria apetala Helianthus atrorubens subsp. radula