Helianthus angustifolius L.

Swamp sunflower (en)

Species

Angiosperms > Asterales > Asteraceae > Helianthus

Characteristics

Perennials, 50–150+ cm (with crown buds, rhizomes absent or poorly developed). Stems erect, usually ± hairy. Leaves mostly cauline; opposite or alternate; sessile or subsessile; blades (3-nerved near bases) narrowly lanceolate to linear, 8–15 × 0.15–0.5(–1) cm, bases cuneate , margins entire (revolute, abaxial face sometimes obscured by rolled margins), abaxial faces strigose to hispid or hirsute, sometimes (adaxial not) gland-dotted. Heads 3–16. Peduncles 5–15 cm. Involucres shallowly hemispheric, 10–20 mm diam. Phyllaries 25–32 (loose), lanceolate, 4–9 × 1–2 mm, apices acute to slightly acuminate, abaxial faces usually scabrous, rarely glabrous, usually gland-dotted. Paleae (oblanceolate) 5.5–6.5 mm, entire or ± 3-toothed (apices purplish, mucronate, gland-dotted). Ray florets 10–20; laminae 10–20 mm (abaxial faces gland-dotted). Disc florets 75+; corollas 4–4.5 mm, lobes yellow; anthers dark brown or black, appendages dark (style branches usually yellow). Cypselae 2–3 mm, glabrate; pappi of 2 aristate scales 1.5–2.1 mm. 2n = 34.
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Fibrous-rooted perennial with crown-buds, nearly or quite without rhizomes; stem solitary, 0.5–1.5(–2) m, ± hairy, especially below; lvs numerous, sessile or nearly so, commonly alternate except near the base, linear or nearly so and revolute-margined, mostly 5–15(–20) cm × 2–10(–15) mm and 10–30 times as long as wide, dark green and scabrous above, pale beneath with fine, loose, sometimes deciduous hairs, and often also atomiferous-glandular; petiolate basal lvs with broader blade sometimes present; disk red-purple (yellow), (1–)1.5–2 cm wide; invol bracts narrow, at least the inner with loose, narrow tip seldom surpassing the disk; rays (8–)10–15(–21), 1.5–3 cm; 2n=34. Swamps and moist places; L.I. to Fla. and Tex., chiefly near the coast in our range, but inland to s. O., s. Ind., and s. Mo. Aug.–Oct.
Life form perennial
Growth form herb
Growth support free-standing
Foliage retention deciduous
Sexuality hermaphrodite
Pollination -
Spread -
Mature width (meter) 1.0 - 1.5
Mature height (meter) 1.6 - 1.85
Root system fibrous-root rhizome
Rooting depth (meter) 0.2
Root diameter (meter) 0.5
Flower color
Blooming months
JanFebMar
AprMayJun
JulAugSep
OctNovDec
Fruit color -
Fruiting months -
Nitrogen fixer -
Photosynthetic pathway -

Environment

Light 5-8
Soil humidity 4-6
Soil texture 1-4
Soil acidity 2-7
Soil nutriment -
Hardiness (USDA) 6-9

Usage

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

Cultivation

Can be grown by cuttings, divisions or seedlings.
Mode cuttings divisions seedlings
Germination duration (days) 9 - 14
Germination temperacture (C°) 21
Germination luminosity -
Germination treatment -
Minimum temperature (C°) -
Optimum temperature (C°) -
Size -
Vigor -
Productivity -

Images

Leaf

Helianthus angustifolius leaf picture by Chris Griggs (cc-by-sa)
Helianthus angustifolius leaf picture by Brad Kelley (cc-by-sa)

Flower

Helianthus angustifolius flower picture by Luke Luke (cc-by-sa)
Helianthus angustifolius flower picture by Mr. G Roberts (cc-by-sa)
Helianthus angustifolius flower picture by Jeb Trayer (cc-by-sa)

Distribution

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

Identifiers

LSID urn:lsid:ipni.org:names:315752-2
WFO ID wfo-0000066553
COL ID 3K5TR
BDTFX ID -
INPN ID -
Wikipedia (EN) Link
Wikipedia (FR)

Synonyms

Coreopsis angustifolia Rudbeckia angustifolia Helianthus angustifolius Leighia bicolor Discomela angustifolius Helianthus angustifolius var. planifolius Helianthus angustifolius subsp. angustifolius Helianthus angustifolius var. angustifolius