Silphium radula Nutt.

Roughstem rosinweed (en)

Species

Angiosperms > Asterales > Asteraceae > Silphium

Characteristics

Plants caulescent, 30–250 cm; fibrous rooted. Stems terete, scabrous, hispid, or hirsute. Leaves: basal persistent or caducous, petiolate; cauline alternate or opposite, petiolate or sessile; blades lanceolate to ovate, 2–22 × 0.5–8 cm, bases attenuate to round, margins coarsely dentate or entire, apices acuminate to acute, faces scabrous, hispid, or hirsute. Phyllaries 18–37 in 2–4 series, outer appressed or reflexed, apices acute, abaxial faces scabrous. Ray florets 12–30+; corollas yellow. Disc florets 100–175; corollas yellow. Cypselae 10–17 × 7–15 mm; pappi 2–5 mm.
Life form perennial
Growth form herb
Growth support free-standing
Foliage retention -
Sexuality hermaphrodite
Pollination -
Spread -
Mature width (meter) -
Mature height (meter) 0.4 - 2.5
Root system fibrous-root
Rooting depth (meter) -
Root diameter (meter) -
Flower color
Blooming months
JanFebMar
AprMayJun
JulAugSep
OctNovDec
Fruit color -
Fruiting months -
Nitrogen fixer -
Photosynthetic pathway -

Environment

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

Usage

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

Cultivation

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

Images

Leaf

Silphium radula leaf picture by K. R. (cc-by-sa)
Silphium radula leaf picture by Railey (cc-by-sa)

Flower

Silphium radula flower picture by K O (cc-by-sa)
Silphium radula flower picture by Railey (cc-by-sa)

Distribution

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

Identifiers

LSID urn:lsid:ipni.org:names:249173-1
WFO ID wfo-0000019451
COL ID 6Z2M3
BDTFX ID -
INPN ID -
Wikipedia (EN) Link
Wikipedia (FR)

Synonyms

Silphium reverchonii Silphium simpsonii var. wrightii Silphium radula var. radula Silphium radula

Lower taxons

Silphium radula var. gracile