Occurrence of Spongospora Subterranea in an Area of Improved Pasture at Barrington Tops, New South Wales.

1989 ◽  
Vol 18 (1) ◽  
pp. 17 ◽  
Author(s):  
DB Letham ◽  
JA Murison ◽  
A Francis ◽  
PG Kennedy

1965 ◽  
Vol 16 (6) ◽  
pp. 981 ◽  
Author(s):  
J Lax ◽  
Turner H Newton

The influence of sex, strain, location, and age of ewe on survival rate to weaning of single-born Merino lambs has been examined in two sets of data: the strain trial, involving five strains run without selection at each of three locations (Cunnamulla, Qld.; Armidale, on the northern tablelands of New South Wales; Deniliquin, in the Riverina area of New South Wales), with six age groups of ewes; and the same five strains later included in selection groups at Armidale with seven age groups of ewes. The strain trial at Armidale ran mainly on native, and the selection groups mainly on improved pastures. Female lambs had a higher survival rate than either castrated or entire males, the differences in lambs weaned per lamb born being 0.03 and 0.04 respectively. No strain differences could be regarded as statistically significant, and neither could the strain x location interaction in the strain trial. Mean survival rates for the strains ranged from 0.673 to 0.786 on the Armidale native and from 0.802 to 0.850 on the Armidale improved pasture, from 0.746 to 0.859 at Cunnamulla, and from 0.838 to 0.894 at Deniliquin. The strains did not rank consistently in the same order. Location had a marked effect on survival rate, the means being 0.744 for the native and 0.824 for the improved pasture at Armidale, 0.810 at Cunnamulla, and 0.868 at Deniliquin. Age of ewe had a marked influence in the poorest environment (Armidale native pasture), survival rate rising with age and later falling sharply. The effect was less marked in the intermediate environments (Armidale improved pasture and Cunnamulla) and negligible at Deniliquin. The patterns at Cunnamulla and Deniliquin are confirmed by data from other experiments on these stations. Survival rate is one component of number of lambs weaned. The other component, number of lambs born, has a higher mean value at Deniliquin than Cunnamulla, but shows a strong association with age of ewe in both environments. Number of lambs born responds rapidly to selection, but no information is yet available concerning the likely response in survival rate. If improvement in environment can raise the survival rate, particularly in the youngest and oldest ewes, then selection for number of lambs born, combined with improved environment, should lead to a marked rise in the number of lambs weaned.



2002 ◽  
Vol 42 (2) ◽  
pp. 143
Author(s):  
D. L. Michalk ◽  
M. H. Campbell

Aerial sowing is the only option for introducing improved pasture species into much of the non-arable, acid soil rangelands in central New South Wales. However, low germination of seeds in serradella pods is a major problem causing poor establishment. Sowing different combinations of pod and seed was investigated as a means of improving germination and subsequent persistence in an experiment between 1993 and 1997. Results indicated that a pod:seed mixture of 75:25 was the most suitable ratio for establishing yellow serradella (Ornithopus compressus) when broadcast into native grassland on hardsetting, non-arable, acidic hill country. Nodulation failure observed at this cold tablelands site confirmed the need for a more winter-active inoculant for yellow serradella.





1962 ◽  
Vol 13 (6) ◽  
pp. 1059 ◽  
Author(s):  
JR Simpson

Soils under improved pasture on the Southern Tableland of New South Wales accumulated nitrate in substantial quantities during the summer and autumn. In this respect they behaved quite unlike the pasture soils which have been studied in most of the earlier literature, and they resembled cultivated fallow soils, which usually accumulate nitrate at the same time of the year. The nitrate was produced mainly in the top inch of soil; ammonium also accumulated under certain conditions. The precise sequence of climatic events, particularly the period of drying between consecutive wettings, was of primary importance in the nitrate accumulation. The nitrate produced during summer and early autumn disappeared from the topsoil after heavy rain in autumn and winter. The seasons could therefore be distinguished as a nitrogen-rich summer and autumn, a nitrogen-depleting winter, and a nitrogen-poor early spring, with an increasing supply of mineral nitrogen during late spring. No appreciable fluctuations in mineral nitrogen were found in soils resown directly from native pasture with less than 0.10% total nitrogen at 0-2 in.



1976 ◽  
Vol 27 (1) ◽  
pp. 63 ◽  
Author(s):  
RCG Smith ◽  
MJ Stephens

A simple model for predicting pasture growth from climatic data was developed and tested against experimental data. The model was used to analyse climatic data from a 24-yr period (1950–1973) to elucidate the relative importance of soil moisture and temperature on the growth of improved pastures on the Northern Tablelands of New South Wales, and to predict the year-to-year variations in total pasture growth.Predicted yearly dry matter production varied between extremes of 5000 kg ha-1 yr-1 in 1965 and 14,000 kg ha-1 yr-1 in 1971. Soil moisture was the major factor limiting pasture growth from the beginning of October until the end of May, and temperature was the major limiting factor from the end of May to early October. During May and October there was a period when both factors had a similar probability of being the most limiting factor. Variations in soil moisture caused greater within-year variability in pasture growth than temperature except in April and September when variability caused by temperature equalled that caused by soil moisture. The significance of these effects is discussed.



1979 ◽  
Vol 19 (99) ◽  
pp. 476 ◽  
Author(s):  
MH Campbell ◽  
AR Gilmour ◽  
DT Vere

The effects of time and rate of application of tetrapion on burnt and unburnt serrated tussock, growing with and without improved species, were measured in four experiments carried out near Bathurst, New South Wales, between 1975 and 1978. Tetrapion proved effective in killing unburnt serrated tussock when applied in each season of the year. The most economical rates proved to be 1.00 kg a.i, ha-1 in spring and summer and 1.33 kg a.i. ha-1 in autumn and winter. Tetrapion was also effective in killing serrated tussock that had been burnt six and nine months before spraying. Although tetrapion had harsh phytotoxic effects on Phalaris aquatica and Trioflium repens growing in association with serrated tussock, these improved species recovered. Thus it proved possible to selectively remove serrated tussock from P. aquatica and T. repens by using tetrapion. Based on 1979 costs, tetrapion appears an economic alternative to other herbicides currently used to kill serrated tussock.



1975 ◽  
Vol 15 (73) ◽  
pp. 149
Author(s):  
DW Hennessy ◽  
GG Robinson

To overcome a winter-sp nes, New South Wales forage oats were sown into forty-five per cent of improved pasture (mainly Phalaris tuberosa and Trifolium repens) areas and the liveweight gains of weaner cattle grazing these areas from March to October were compared with those grazing pasture only. Three methods for managing the grazing of the forage oats were compared in 1971, and in 1972 the effect of an oat grain supplement on liveweight gain of cattle grazing either pasture only or pasture and forage oats was measured. Weaners did not reach 270 kg by October, the objective mean liveweight, in any of the treatments or years. Neither did forage oats significantly increase beef production from pasture, but when properly managed did reduce the need for hay supplements to maintain weaner liveweight during winter. Although the stocking rate of 2.82 weaners ha-1 from March to October was apparently too high in 1971 to allow adequate liveweight gains, the forage oats and pasture were best utilized by allowing weaners to graze freely between paddocks. Oat grain supplements in 1972 did improve weaners' liveweights (at intakes of 1 .O-2.0 per cent liveweight) but reduced the relative economic return from either the pasture or pasture and forage oat areas. We concluded from the study that forage oats sown into improved pasture areas did not increase feed availability in the latter part of the feed-gap nor reliably increase beef production from pasture at the stocking rate studied.



1979 ◽  
Vol 19 (99) ◽  
pp. 472 ◽  
Author(s):  
MH Campbell ◽  
AR Gilmour

The effect of three rates of glyphosate (1, 3 and 5 kg a.i. ha-1) and two of 2,2-DPA (21 and 33 kg a.i. ha-1), each applied in October 1972, January 1973, April 1973 and July 1973, on serrated tussock and associated improved species (Phalaris aquatics, Trifolium repens, T. subterraneum) was ascertained in an experiment near Bathurst, New South Wales. The effect of the herbicide treatments on the improved species was measured in October 1973 and the percentage kill of serrated tussock recorded in May 1974. Increasing the rate of glyphosate increased the percentage kill of serrated tussock (up to a mean of 77% with 5 kg a.i. ha-1) ; time of application had no significant effect on percentage kill. No glyphosate treatment resulted in a commercially acceptable kill of serrated tussock (above 90%). Thus the herbicide was inferior to 2,2-DPA which produced a 95% kill when applied in summer. P. tuberosa was more tolerant of glyphosate and 2,2-DPA than serrated tussock and recovered from all treatments. T. repens and T. subterraneum recovered from glyphosate and 2,2-DPA applied in summer. Thus it proved possible to selectively remove a large proportion of a serrated tussock infestation with 2,2-DPA or glyphosate, applied in summer, without permanent damage to the associated improved species.



Sign in / Sign up

Export Citation Format

Share Document