Helianthus grosseserratus

M. Martens

Index Seminum (Louvain) 1839: unpaged. 1839.

Common names: Sawtooth sunflower hélianthe à grosses dents
Endemic
Synonyms: Helianthus instabilis E. Watson
Treatment appears in FNA Volume 21. Treatment on page 165. Mentioned on page 146, 166.

Perennials, 100–400 (–500) cm (rhizomatous). Stems erect, glabrous proximally, distally glabrate, scabrellous, or strigillose (glaucous). Leaves cauline; opposite (proximal) or alternate; petioles (1–) 2–5 cm; blades (light to dark green, 3-nerved distal to bases) lanceolate to lanceovate, 10–32 × (1.2–) 4–9 cm, bases cuneate, margins usually coarsely to shallowly serrate, rarely subentire (flat), abaxial faces puberulent to tomentulose, glanddotted. Heads 3–15+. Peduncles 0.3–10 cm. Involucres broadly hemispheric, 15–25 mm diam. Phyllaries 25–30 (loose, spreading), lance-linear, 10–14 × 1.5–2.5 mm (subequal), (margins ± ciliate) apices attenuate, abaxial faces glabrous or puberulent, not glanddotted. Paleae 7–8 mm, entire or 3-toothed (apices acuminate, ± hairy). Ray-florets 14–20; laminae 23–40 mm. Disc-florets 100+; corollas 5–6 mm, lobes yellow; anthers dark-brown to black, appendages yellow. Cypselae 3–4 mm, glabrate; pappi of 2 aristate scales 1.9–2.5 mm. 2n = 34.


Phenology: Flowering late summer–fall.
Habitat: Dry to wet prairies, other open sites
Elevation: 10–300+ m

Distribution

V21-399-distribution-map.gif

Ont., Que., Ark., Conn., Del., D.C., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.H., N.J., N.Y., N.C., N.Dak., Ohio, Okla., Pa., S.Dak., Tenn., Tex., Va., Wash., W.Va., Wis.

Discussion

Helianthus grosseserratus is native to midwestern North America and has spread as a roadside weed into other areas, such as New England and the southeastern United States. It is introduced in Canada. Hybrids between H. maximiliani and H. grosseserratus are known as H. ×intermedius R. W. Long (R. W. Long 1954; Long 1966). Hybrids of H. grosseserratus with H. salicifolius have been described as H. kellermannii Britton (Long 1955), and those with H. mollis as H. brevifolius E. Watson (R. C. Jackson and A. T. Guard 1957b).

Selected References

None.

Lower Taxa

None.

... more about "Helianthus grosseserratus"
puberulent +, glabrous +  and tomentulose +
not tailed +, rounded +  and obtuse +
dark-brown +  and black +
pale +  and dark +
connate +  and distinct +
subequal +
scarious +
usually ovate +  and lanceolate +
usually deltate +  and lanceolate +
spiciform +, paniculiform +  and corymbiform +
indeterminate +  and determinate +
Edward E. Schilling +
M. Martens +
cuneate +
1.2 cm12 mm <br />0.012 m <br /> (4 cm40 mm <br />0.04 m <br />) +
10 cm100 mm <br />0.1 m <br /> (32 cm320 mm <br />0.32 m <br />) +
lanceolate;lanceovate +
4cm;9cm +
winged;ribbed;winged;ribbed +
tuberculate +  and rugose +
barbellulate +  and barbellate +
Sawtooth sunflower +  and hélianthe à grosses dents +
reddish +  and yellow +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
compressed +  and obpyramidal +
fertile +  and bisexual +
fertile +  and bisexual +
Ont. +, Que. +, Ark. +, Conn. +, Del. +, D.C. +, Ga. +, Ill. +, Ind. +, Iowa +, Kans. +, Ky. +, La. +, Maine +, Md. +, Mass. +, Mich. +, Minn. +, Miss. +, Mo. +, Nebr. +, N.H. +, N.J. +, N.Y. +, N.C. +, N.Dak. +, Ohio +, Okla. +, Pa. +, S.Dak. +, Tenn. +, Tex. +, Va. +, Wash. +, W.Va. +  and Wis. +
10–300+ m +
hairy +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Dry to wet prairies, other open sites +
in more or less corymbiform , paniculiform or spiciform , arrays +  and singly +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
1.5 cm15 mm <br />0.015 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
hemispheric +
2.3 cm23 mm <br />0.023 m <br /> (4 cm40 mm <br />0.04 m <br />) +
sessile +  and petiolate +
alternate +  and opposite +
triangular +
subentire +
2-carpellate +
3-toothed;entire +
0.7 cm7 mm <br />0.007 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
persistent +
coroniform +
0.3 cm3 mm <br />0.003 m <br /> (10 cm100 mm <br />0.1 m <br />) +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
2 cm20 mm <br />0.02 m <br /> (5 cm50 mm <br />0.05 m <br />) +
Flowering late summer–fall. +
1 cm10 mm <br />0.01 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
25 +  and 30 +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
Index Seminum (Louvain) +
bearing subulate enations +, hairy +  and bristly +
flat;slightly convex +
aristate +
0.19 cm1.9 mm <br />0.0019 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
exalbuminous +
procumbent +  and decumbent +
scabrellous +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
Helianthus instabilis +
Helianthus grosseserratus +
Helianthus +
species +
campanulate +
toothed +  and entire +
400 cm4,000 mm <br />4 m <br /> (500 cm5,000 mm <br />5 m <br />) +
100 cm1,000 mm <br />1 m <br /> (400 cm4,000 mm <br />4 m <br />) +
shrub +  and subshrub +