SPECIES DESCRIPTION
TRIFOLIUM SUBTERRANEUM
Family and Genus:- See- LEGUMINOSAE/Sect. TRICHOCEPHALUM
Common Names:- Burrowing clover
Homotypic Synonyms:- Calycomorphum subterraneum, Trifolium
subterraneum var. genuinum, Trifolium subterraneum var. typicum,
Triphylloides comosa.
Meaning:- Trifolium (L) With three leaflets.
Subterraneum (L) Below ground, underground.
General description:- Sparsely hairy, procumbent annual.
Stems:-
1) Up to 20(-30) cm, numerous, procumbent, usually patent-pilose.
Leaves:-
1) Long-petiolate.
2) Leaflets, obovate to obcordate, often with dark blotches. usually long petiolate.
3) Stipules, ovate, acute, free part rather short and broad.
Flowers:-
1) Fruiting-heads, globose, appressed to or buried in the soil by the long, deflexed
peduncle.
2) Fertile flowers, 2-5(-7), ebracteate, but heads sometimes involucrate.
3) Sterile flowers, lacking a corolla and with a solid calyx tube developing after
anthesis, becoming deflexed over the fruiting calyces. Developing fruiting
heads pushed into the ground by the elongating, arching peduncle.
4) Peduncles, shorter than the leaves at anthesis.
5) Calyx tube, cylindrical, obscurely veined;
a) teeth, subequal, subulate, somewhat exceeding the tube.
b) throat, usually ± closed by a ring of hairs or an annular or bilabiate callosity at
maturity.
5) Corolla, 8-14 mm, much exceeding calyx, cream, often flushed pink on the
standard.
Fruit:-
1) Legume, 1(-2)-seeded, almost always included in the calyx-tube.
1) Seeds, prolonged cordiform, radicle, approximately as long as the cotyledons,
3.2 - 3.8 x 2.4 - 2.8, surface smooth, slightly lustrous black.
Key features:-
1) Flowers, ebracteate but heads sometimes involucrate.
2) Legume, 1(-2)-seeded, almost always included in the calyx-tube.
3) Fertile flowers 2-12; inner flowers consisting only of sterile calyces developing
either at or after anthesis from a central nodule;
4) Fruiting heads, appressed to the ground or subterranean.
Habitat:- Coastal flats, patches of meadow in dry open shrubby vegetation and
open wood-land, olive groves. 0-800 m. (-1500 m. in dolines).
Distribution:- Throughout Greece, west Europe, Mediterranean area and SW.Asia,
widespread in C. And S. Europe. Widespread on Crete but mainly central and west.
Flowering time:- Mar-June.
Photos by:- Dr. Armin Jagel
