CALENDULA ARVENSIS
Common Name:- Field marigold
Synonyms:- Caltha arvensis.
Meaning:- Calendula (L) First-day-of-the-month.
Arvensis (L) Of the cultivated or ploughed field.
General description:- Annual, often thinly covered with fine interlaced woolly tufts
of hairs resembling a spider's web.
Stem:-
1) (5-)15-25(-30)cm, erect or diffuse, usually much-branched.
Leaves:-
1) Alternate, simple, (1-)3-8(-10) x 0·4-1·4(-2) cm, pubescent, or thinly floccose,
oblong or narrowly obovate, acute or obtuse, with subentire or denticulate
margins.
Flowers:-
1) Capitula from 10 to 27mm. diam. In fruit usually with an outer row of incurved,
narrowly beaked achenes 1·3-2 cm, alternating with cymbiform achenes 0·6-
1cm.
2) Disk-florets having only male organs.
3) Ray-florets having only female organs and laid out on 2 or 3 rows.
4) Ligules yellow or orange, usually less than 1·8 cm, often distinctly exceeding,
but not twice as long as the involucral bracts.
5) Involucre bracts, pale green, seldom orange, reddish or purple at the top, finished
by a very small point.
Fruit:-
1) Achenes, none feathery, sometimes coiled in a ring, crest spiny or tuberculate.
2) External achenes with a very curved beak.
Key features:-
1) Ligules usually less than twice as long as involucral bracts.
2) Outer achenes with a narrow beak or cymbiform, not 3-winged.
Habitat:- Common weed of fallow fields, olive groves, roadsides and ruderal
habitats. 700(-1200) m.
Distribution:- Widespread and common throughout the Mediterranean. Widespread
and common on Crete.
Flowering time:- Almost throughout year but mainly Mar-May.
Photos by:- Steve Lenton