Glycine tabacina (Labill.) Benth.


Leguminosae Synonyms
Kennedya tabacina Labill.; Leptolobdum elongatum Benth.; L. tabacinum (Labill.) Benth.; Leptocyamus elongatus Benth.; Desmodium novo-hollandicum F. Muell.
Common names
Pea glycine; variable glycine; slender sweetroot (Australia) .
A prostrate perennial legume. Stems slender and elongated, usually creeping or trailing, occasionally twining, retrorsely strigose to glabrous, the vestiture usually white. Stems arising from a woody, often thickened root-stock. Leaves pinnately trifoliate. Petioles 5 to 45 mm long, the rachis 1 to 4 mm long. Stipules deltoid to oblong-lanceolate, 1.5 to 3 mm long, obtuse to acuminate, coarsely several ribbed, sparsely strigose to glabrous. Leaflets thin, generally strigose beneath, sparingly strigose to glabrous above. Terminal leaflet often larger and longer than the laterals. Leaflets of the lower leaves usually broadly obovate to oval, 10 to 15 x 8 to 14 mm, obtuse to truncate, occasionally emarginate, apiculate or acute, tapering at the base, often prominently net veined beneath. Leaflets of the upper leaves usually elliptic-lanceolate to narrowly oblong-lanceolate or linear, 7 to 50 mm long, 3 to 7 mm wide, acute to blunt and apiculate, abruptly tapering to rounded at the base. Petiolules 1 to 2 mm long, hirsute. Occasionally all the leaves oval to broadly oblong, 20 to 40 mm long, 10 to 20 mm wide. Racemes in the upper axils, slender, elongate, 2 to 8 cm long, loosely 4- to 12-flowered on sparsely strigose to glabrous peduncles, 2 to 12 cm long. Flowers in the lower axils often solitary or in few-flowered fascicles. Flowers 6 to 8 mm long on pedicels 0.5 to 2 mm long and frequently subsessile. Calyx 3 to 4.5 mm long, usually sparsely strigose to glabrous, occasionally densely strigose or short-hirsute, the teeth from broadly to narrowly lanceolate, the same length or shorter than the tube. Corolla blue to violet or purplish. Standard obovate reflexed to ascending, slightly longer than the obovate-oblong wings which conspicuously exceed the keel. Pods linear, 14 to 30 mm long, 3 to 3.5 mm wide, compressed, the persistent style variously hooked or curved, three- to six- seeded. Seeds 1.75 to 3 x 1.75 mm, oblong to ovoid, often truncate at the ends, smooth and dull to glossy, muriculate, purplish black in colour (Hermann, 1962).
Pea glycine is native from southern Australia through the tropics of northern Australia, South Pacific islands such as Tonga, Fiji and New Caledonia to as far north as Fujian Province, China. It is found in rocky pastures, clearings, dry hillsides and sandy slopes (Hermann, 1962).
General features
Pea glycine is probably the commonest and most widely distributed of the native legumes that are of forage value in eastern Australia, being almost cosmopolitan in its occurrence. It does particularly well on sandy soils but is also found on the black basaltic clays. Intermediates between G. tabacina and G. clandestina are frequent where the two species occur together.
No toxic features have been recorded for pea glycine and it is readily eaten. It is not however highly productive, but is probably selectively grazed in pastures when stock are present. It responded to applied phosphate at Armidale, New South Wales, Australia, but not as strongly as naturalized legumes or Lespedeza cuneata. It did not respond to applied sulphur (Begg, 1963).
Pea glycine was intermediate between G. falcata and G. tomentella in reaction to artificial salinity applied for ten days in the five-trifoliate leaf stage (Wilson, Haydock and Robins, 1970). It is known to nodulate (Bowen, 1956).