23.
Bidens connata
Muhlenberg ex Willdenow, Sp. Pl. 3: 1718. 1803.
Bident conné
Bidens connata
var.
ambiversa
Fassett;
B. connata
var.
anomala
Farwell;
B. connata
var.
fallax
(Warnstorf) Sherff;
B. connata
var.
gracilipes
Fernald;
B. connata
var.
inundata
Fernald;
B. connata
var.
petiolata
(Nuttall) Farwell;
B. connata
var.
pinnata
S. Watson;
B. connata
var.
submutica
Fassett
Annuals,
(5—)25—150(—200) cm.
Leaves:
sessile or petioles (± winged) 5—15(—35+) mm; blades ± elliptic to lanceolate, (20—)40—100(—200+) × 10—30(—70) mm, sometimes laciniately 1-pinnatisect with 1—4+ lobes near bases, bases cuneate, margins entire or dentate to serrate, usually ciliate, apices attenuate, faces glabrous or hirtellous.
Heads
borne singly or in 2s or 3s.
Peduncles
10—35(—80) mm.
Calyculi
of 2—6+ spreading or ascending, lanceolate, linear, oblanceolate, oblong, or spatulate, ± foliaceous bractlets or bracts 10—25(—35+) mm, margins (entire or serrate) usually ciliate, abaxial faces hispidulous near bases, distally glabrous.
Involucres
campanulate to hemispheric or broader, (4—)6—12 × (3—)6—9(—15+) mm.
Phyllaries
(6—)8(—9), elliptic to oblong or ovate, (4—)5—6(—12) mm.
Ray florets
usually 0, sometimes 1—5+; laminae yellowish, 4—8 mm.
Disc florets
(5—)20—40(—60+); corollas pale yellow to orange, 2—3 mm (± abruptly ampliate, anthers usually dark, blackish).
Cypselae
blackish to purplish or brown, usually (at least inner) ± 4-angled, usually cuneate to linear, sometimes ± obpyramidal, outer (3—)4—7 mm, inner (4—)5—8 mm, margins proximally antrorsely to patently, distally retrorsely, barbed, apices ± truncate to concave, faces usually strongly 1-nerved, usually tuberculate, glabrous or setulose;
pappi
0, or of (1—)2—4(—6), ± erect to spreading, antrorsely or retrorsely barbed awns (0.2—)2—5 mm.
2
n
= 48.
Flowering Aug—Oct. Marshes and other wet sites; 10—1700 m; N.B., Nfld. and Labr. (Nfld.), N.S., Ont., P.E.I., Que.; Conn., Del., Ga., Ill., Ind., Iowa, Kans., Ky., Maine, Md., Mass., Mich., Minn., Mo., Mont., Nebr., N.H., N.J., N.Y., N.C., N.Dak., Ohio, Pa., R.I., S.C., S.Dak., Tenn., Va., W.Va., Wis.; Europe; Asia; n Africa; introduced in Pacific Islands, Australia.
Bidens connata
may be better treated as part of
B. tripartita
.
