Trifolium dubium Sibth.
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Trifolium dubium Sibth.
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Leguminoseae Common names Yellow suckling clover, lesser yellow trefoil, red suckling clover, little or small hop clover. |
Author:
Dr. John Frame
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Sub-erect to prostrate annual, glabrous to slightly pubescent foliage with slender, wiry stems, 0.3-0.6 m, branched at the base. On the stems there are sometimes downy hairs which turn red with age. Grey-green, narrow leaflets are triangular and broadest at the apex; terminal leaflet stalked; broad-based stipules are sharply pointed. Has short tap root but a mass of fibrous roots in upper soil layers. Inflorescences, borne on axillary stalks, are round racemes each with 12-30 lemon yellow florets which become reversed after flowering. Self sterile flowers. Oval-shaped seeds, yellow to olive in colour, borne singly in seed pods. Distribution Indigenous to Europe. Naturalises on shallow, coarse-textured soils in dry conditions. Has spread to cool and warm temperate grasslands elsewhere as a wild plant. Became used as a minor constituent in seed mixtures for dry areas and, for example, as a winter annual on acid, sandy soils in southern USA. Resident in infertile, northern-aspect hill country in New Zealand (Kemp et al., 1999). Season of growth Contributes to pasture yield mainly in spring/early summer. Frost tolerance Under a technique which artificially frosted the shoots (temperatures of -4 to -160C in controlled environment experimentation), suckling clover was among the most frost tolerant of 13 Trifolium species evaluated (Caradus, 1995). Drought tolerance Low to medium tolerance to prolonged drought (Keoghan and Allan, 1992). Soil requirements Adapted to dry, coarse-textured soils, but also to wet, acid and infertile soils in southern New Zealand (Keoghan and Allan, 1992). Not competitive in well-fertilised, intensively-managed swards. Ability to spread naturally Seems to have a good ability where conditions suit it. Persists through self-seeding. Seeds have a strong germinative capacity even in dry conditions. Sowing No longer recommended in most temperate countries for inclusion in seed mixtures. Was used in the past at 2-4 kg/ha in seed mixtures for dry, coarse-textured, low-fertility soils. Number of seeds per kg Circa 2 000 000. Response to defoliation Tolerates set stocking moderately well (Keoghan and Allan, 1992). Dry matter yields Low productivity. Has produced 1 t/ha of fine leafy hay if cut before seed formation (Knight, 1985b). Main attributes Can contribute to sward yield in early season especially on dry, infertile soils. Frost tolerant. Main shortcomings Low productivity. Not a suitable species for well-fertilized, intensively-managed, swards based on sown productive species. Links
References Caradus J.R. (1995); Kemp P.D. et al. (1999); Keoghan J. and Allan B. (1992); Knight W.E. (1985b) |