1.
Anthemis arvensis
Linnaeus, Sp. Pl. 2: 894. 1753.
Corn chamomile, fausse camomille, anthémis des champs
Anthemis arvensis
var.
agrestis
(Wallroth) de Candolle;
Chamaemelum arvense
(Linnaeus) Hoffmannsegg & Link
Annuals
(sometimes persisting), (5—)10—30+[—80] cm, not notably scented.
Stems
green or reddish, decumbent (sometimes rooting at nodes) or ascending to erect, branched mostly proximally, ± strigoso-sericeous or villous, glabrescent.
Leaf blades
15—35 × 8—16 mm, 1—2-pinnately lobed (ultimate lobes triangular to narrowly elliptic or linear).
Peduncles
mostly 4—15 cm (sometimes clavate in fruit).
Involucres
6—13 mm diam., ± villous.
Receptacles
paleate throughout; paleae lanceolate to oblanceolate, weakly navicular (± carinate), 3—4+ mm (including acuminate-spinose tips).
Ray florets
5—20, pistillate, fertile; corollas white, rarely tinged with pink, laminae 5—15 mm.
Disc corollas
(sometimes tinged with purple) 2—3(—4) mm.
Cypselae
1.7—2+ mm, ribs smooth or weakly tuberculate (sometimes separated by relatively deep furrows);
pappi
0 or coroniform (0.01+ mm).
2
n
= 18.
Flowering May—Jul(—Sep). Disturbed sites, abandoned plantings; 10—400+ m; introduced; B.C., N.B., Nfld. and Labr. (Nfld.), N.S., Ont., P.E.I., Que.; Ala., Calif., Colo., Conn., Del., D.C., Fla., Ga., Idaho, Ill., Ind., Iowa, Ky., La., Maine, Md., Mass., Miss., Mo., Nebr., N.H., N.J., N.Y., N.C., N.Dak., Ohio, Oreg., Pa., R.I., S.C., Tenn., Vt., Va., Wash., W.Va., Wyo.; Europe.
Anthemis arvensis
is morphologically variable; it is found throughout much of North America.
