Bidens trichosperma

(Michaux) Britton

Bull. Torrey Bot. Club 20: 281. 1893.

Endemic
Basionym: Coreopsis trichosperma Michaux Fl. Bor.-Amer. 2: 139. 1803
Synonyms: Bidens coronata var. brachyodonta Fernald Bidens coronata var. tenuiloba (A. Gray) Sherff Bidens coronata var. trichosperma (Michaux) Fernald
Treatment appears in FNA Volume 21. Treatment on page 213. Mentioned on page 207.

Annuals (biennials), (15–) 30–50 (–150+) cm. Leaves: petioles 5–20+ mm; blades ± deltate to ovate overall, 40–75 (–150) × 10–45 (–130) mm, usually laciniately 1–2-pinnatisect, ultimate lobes (3–) 5–7+, oblanceolate or lanceolate to linear, (5–) 10–30 (–80+) × (1–) 4–8 (–12+) mm, bases cuneate, ultimate margins incised, dentate, serrate, or entire, little, if at all, ciliate, apices acute to attenuate, faces glabrous or ± hirtellous to strigillose. Heads usually in open, ± corymbiform arrays. Peduncles 20–150 mm. Calyculi of (6–) 8 (–11), ascending to spreading, spatulate to linear, sometimes ± foliaceous bractlets or bracts 3–10 (–18) mm, margins sometimes ciliate, abaxial faces glabrous. Involucres hemispheric or broader, 4–6 (–8) × 6–12 mm. Phyllaries 6–8 (–10), oblong, 3–8 mm. Ray-florets (7–) 8–9; laminae golden yellow, 10–30 mm. Disc-florets 40–60 (–80+); corollas yellow, 3–5 mm. Cypselae blackish or brown, flattened, narrowly cuneate, outer 3–6 mm, inner 5–9 mm (lengths mostly 2.5–4 times widths), margins antrorsely barbed or ciliate, apices ± truncate, faces obscurely 1-nerved, sometimes tuberculate, glabrous or sparsely hispidulous; pappi of 2 erect, ± patently barbed awns or scales (0.4–) 1–2.5 (–4) mm. 2n = 24.


Phenology: Flowering Aug–Oct.
Habitat: Marshes, estuaries
Elevation: 0–300 m

Distribution

V21-518-distribution-map.gif

Ont., Que., Ala., Ark., Conn., Del., Fla., Ga., Ill., Ind., Iowa, Ky., Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.J., N.Y., N.C., Ohio, Pa., R.I., S.C., S.Dak., Tenn., Va., W.Va., Wis.

Discussion

Plants here called Bidens trichosperma have long been known as B. coronata (Linnaeus) Britton (or Britton ex Sherff). Alas, Britton’s B. coronata (1913) is a later homonym of B. coronata Fischer ex Colla (1834) and cannot be used.

Selected References

None.

Lower Taxa

None.
... more about "Bidens trichosperma"
not tailed +, rounded +  and obtuse +
dark +  and pale +
connate +  and distinct +
acute;attenuate +
subequal +
scarious +
usually ovate +  and lanceolate +
usually deltate +  and lanceolate +
indeterminate +  and determinate +
John L. Strother +  and Ronald R. Weedon +
(Michaux) Britton +
ciliate +  and barbellate +
cuneate +
Coreopsis trichosperma +
compound +  and simple +
7.5 cm75 mm <br />0.075 m <br /> (15 cm150 mm <br />0.15 m <br />) +
4.5 cm45 mm <br />0.045 m <br /> (13 cm130 mm <br />0.13 m <br />) +
4 cm40 mm <br />0.04 m <br /> (7.5 cm75 mm <br />0.075 m <br />) +
less deltate;ovate +
1 cm10 mm <br />0.01 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
winged;ribbed;winged;ribbed +
tuberculate +  and rugose +
1 cm10 mm <br />0.01 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (1 cm10 mm <br />0.01 m <br />) +
ascending +  and spreading +
spatulate;linear +
barbellulate +  and barbellate +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
brown +  and blackish +
cuneate +  and flattened +
fertile +  and bisexual +
fertile +  and bisexual +
sessile +  and petiolate +
Ont. +, Que. +, Ala. +, Ark. +, Conn. +, Del. +, Fla. +, Ga. +, Ill. +, Ind. +, Iowa +, Ky. +, Md. +, Mass. +, Mich. +, Minn. +, Miss. +, Mo. +, Nebr. +, N.J. +, N.Y. +, N.C. +, Ohio +, Pa. +, R.I. +, S.C. +, S.Dak. +, Tenn. +, Va. +, W.Va. +  and Wis. +
0–300 m +
hispidulous +, glabrous +, more or less hirtellous +  and strigillose +
tuberculate +
linear-fusiform;4-angled;ovate;orbiculate;oblong;linear;cuneate +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Marshes, estuaries +
discoid +  and radiate +
disciform +  and discoid +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
0.5 cm5 mm <br />0.005 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
hemispheric +
0.6 cm6 mm <br />0.006 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
golden yellow +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
sessile +  and petiolate +
whorled +  and opposite +
deltate +
ciliate +  and barbed +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
2-carpellate +
less flat;slightly navicular +
persistent +
of 1-2 , smooth to ciliate or barbed awns or scales +  and coroniform +
2 cm20 mm <br />0.02 m <br /> (15 cm150 mm <br />0.15 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (2 cm20 mm <br />0.02 m <br />) +
Flowering Aug–Oct. +
connate +  and distinct +
0.3 cm3 mm <br />0.003 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
Bull. Torrey Bot. Club +
styliferous +  and neuter +
bearing subulate enations +, hairy +  and bristly +
convex;flat +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
exalbuminous +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
Bidens coronata var. brachyodonta +, Bidens coronata var. tenuiloba +  and Bidens coronata var. trichosperma +
Bidens trichosperma +
species +
3 cm30 mm <br />0.03 m <br /> (8 cm80 mm <br />0.08 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
5 (?) +  and 7 (?) +
lanceolate;linear +
0.4 cm4 mm <br />0.004 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
entire +, serrate +  and dentate +
50 cm500 mm <br />0.5 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
30 cm300 mm <br />0.3 m <br /> (50 cm500 mm <br />0.5 m <br />) +
shrub +  and subshrub +