No abstract

Lotononis bainesii is a prostrate, fine stemmed, small leaved, stoloniferous perennial legume, suitable for pasture mixtures in parts of the sub-tropics and tropics. It prefers moist, friable soils, on which it withstands heavy graying. It is highly palatable and non-toxic to stock and is frost tolerant but virus susceptible. Heavy grazing in late summer reduces virus attack and ensures green growth through the winter. Reproduction is by seed or by vegetative means. The species combines well with a number of pasture grasses. Yields of L. bainesii exceeding one ton of dry matter per acre have been obtained in mid-summer on grazed grass-legume mixtures, and yields of 1/4 ton per acre are common. The mean nitrogen content is approximately 2.9 per cent.

On the coastal lowlands of South Queensland, Lotononis bainesii responded in dry matter yield and potassium content to increasing applications of potassium. It did not respond to additions of sulphur. Higher annual yields were obtained from cutting at 8 or 12 weeks than at 4 weeks. Continued frequent cutting had no permanent adverse effect as measured by a 12-week regrowth after treatments were discontinued. Yield was closely associated with radiation received, with a minimum of about 11,200 Langleys in a 4-week period being required for measurable growth, and radiation provided the best fit of meteorological parameters with seasonal fluctuations in production. Growth did not occur in winter and was not resumed in spring until the weekly mean minimum temperature reached 9�C. The detrimental effect of dense shade on lotononis is discussed.

A complex pasture mixture was grazed by cattle at three stocking rates (1.23, 1.65 and 2.47 beasts a hectare) at Beerwah, south-eastern Queensland over six years. There were four fertilizer treatments involving two rates of superphosphate and three of KCl. On the basis of species frequencies, the seven major soil types on the area fell into two groups, the podzolic soils in one and the humic gleys in another. The podzolics were favoured by Chloris gayana, Desmodium intortum, D. uncinatum and Lotononis bainesii, whereas Paspalum dilatatum and Trifolium repens were more frequent on the humic gleys. The light stocking rate favoured Paspalum commersonii, Digitaria decumbens and both Desmodium species. At the high stocking rate P. dilatatum, T. repens and L. bainesii were more prominent, as were weeds in general. Application of KCl had no effect on botanical composition but the K content of soils and plants increased with increasing levels of application. As the superphosphate rate was increased, the proportion of all sown species except P. dilatatum and L. bainesii increased and the weed content decreased. Over time, the legume content in all plots decreased, weeds increased and the grass content remained about the same. The effects were more marked at low rates of superphosphate and high stocking rate. There was a lower legume content and a higher weed content in winter than in summer, but soils and treatments had similar effects in both seasons. Compared with virgin soils, those under fertilized pastures for eight years contained more organic C, available P, K and Ca, total N, and Zn and Fe.

Animal production was measured over a six-year period from grass-legume pastures receiving different maintenance rates of phosphorus and potassium fertilizers, and continuously grazed at stocking rates of 1.23, 1.65 and 2.47 beasts ha-1. The pastures consisted of the grasses Chloris gayana, Digitaria decumbens, Paspalum dilatatum and P. commersonii and the legumes Desmodium intortum, D. uncinatum, L otononis bainesii, Macrop tilium lath yroides and Trifolium repens. Annual applications of 250 kg ha-1 superphosphate (9.6 per cent P) significantly increased animal production above applications of 125 kg ha-1 superphosphate, but there were no significant effects of increase in level of applied potassium (as KCI) beyond 63 kg ha-1. The greatest liveweight gain per hectare was obtained at a stocking rate of 2.47 beasts ha-1 but rate of liveweight change was more variable than at the other stocking rates. Conversely, daily liveweight gains per head and rate of turnoff were greatest at 1.23 beasts ha-1. Both stocking rates and levels of superphosphate affected quality of carcase produced, and there was a significant positive correlation of liveweight gain and legume content of the pastures.