Helianthus longifolius Pursh

Longleaf sunflower (en)

Species

Angiosperms > Asterales > Asteraceae > Helianthus

Characteristics

Perennials, 10–30 cm (with crown buds). Stems (green or purplish) erect, glabrous. Leaves mostly basal; opposite; petioles 0–1 cm; blades linear to narrowly obovate, 13–30 × 0.7–2 cm, bases cuneate, margins entire or obscurely serrate, faces glabrous, not gland-dotted (cauline smaller). Heads 3–12. Peduncles 4–11 cm. Involucres hemispheric, 8–12 mm diam. Phyllaries 18–23, linear-linear, 5–11 × 1–2.5 mm, (margins ciliolate) apices ± attenuate, abaxial faces glabrate or glabrous. Paleae 6–8 mm, weakly 3-toothed (apices hairy). Ray florets 8–13; laminae 10–19 mm (abaxial faces not gland-dotted). Disc florets 35+; corollas 4.2–5.5 mm, lobes yellow; anthers dark, appendages dark. Cypselae 2–3 mm, glabrate; pappi of 2 aristate scales 1.4–2.5 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) 0.1 - 0.3
Root system -
Rooting depth (meter) -
Root diameter (meter) 0.5
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) 4-9

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 -

Images

Helianthus longifolius unspecified picture

Distribution

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

Identifiers

LSID urn:lsid:ipni.org:names:329241-2
WFO ID wfo-0000116623
COL ID 3K5XZ
BDTFX ID -
INPN ID -
Wikipedia (EN) Link
Wikipedia (FR)

Synonyms

Helianthus longifolius Leighia longifolia