This paper describes a new method for estimating pasture yield in which the yields of random quadrats are rated with respect to a set of reference quadrats preselected in the field to provide a scale which is available for reference throughout the sampling. Three alternative calibration procedures are described based either on the dry matter yields of the reference quadrats or on the yields of quadrats rated and cut either during or at the end of sampling. The second and third procedures are shown to have advantages over the first. When testing the method with four observers and two types of calibration scales, estimates of mean yield were generally within 4 per cent of the actual mean with a maximum difference of 8 per cent. Methods are given for calculating the number of samples required to obtain minimum variance for the estimate of mean yield for a given cost in terms cf time spent in the field.

The results are reported of a study of the effect of annual burning, in the absence of grazing, on the botanical composition of a native pasture in south-eastern Queensland. The main effect of burning was to give dominance of Heteropogon contortus (L.) Beauv. ex R. & S. This appeared to be due to three main causes: established plants were resistant to fire; fire favoured the germination of seed; and fire reduced the basal ground cover of other species. The effects on other species and on the proportion of bare ground are reported. The significance of the results in relation to the present distribution of H. contortus-dominant pastures is discussed.

The performance of Townsville lucerne (Stylosanthes sundaica Taub.) as a legume for inclusion in native pastures dominated by spear grass (Heteropogon contortus (L.) Beauu. ex R. & S.) has been studied near Gladstone, in central coastal Queensland. A pasture mixture of Townsviille lucerne and spear grass, given 10.5 cwt 73 superphosphate, 1.5 cwt potassium chloride, and 5 oz sodium molybdate an acre, over a six-year period: produced five times as much Live-weight gain per acre as untreated native pasture. This increase was a combination of higher carving capacity and greater live-weight gain per head. In addition stock. were marketed at from one to two years earlier than normal. Pot and small replicated field experiments showed that Townsville lucerne responded significantly only to superphosphate and did not require potassium or various trace elements including molybdenum on these soils.

A study of a native pasture of bunch spear grass (HHeteropogon contortus (L.) Beauv.) grazed by beef cattle in subtropical Queensland is reported. The yield and botanical and chemical composition under continuous grazing were recorded over 4 years. Spear grass contributed up to 90 per cent. of the yield of dry matter which ranged from 1 to 2 tons/acre. Approximately 60 per cent. of the total yield was produced between January and April, and there was almost complete absence of growth in the cooler months even when rain occurred. The nutritive value of the forage was low for much of the year, with the crude protein content falling to 2-3 per cent. in the winter. The degree of consumption of forage by stock was low, particularly in the winter, and it was apparent that under the existing form of management the stock had little effect on the pasture. It is concluded that there is little prospect of increasing beef production per acre by grazing management of the native pasture, and that, as the major drawbacks to production stein from the pasture species rather than the climate in which they grow, the logical approach is to replace them by sown grasses and legumes. This involves studies of introduced species and, as many of the soils are of low fertility, attention to plant nutrient deficiencies. Work along these lines is now in progress.

Seventeen introductions representing ten species of Paspalum were compared with naturalized P. dilatatum var. dilatatum in a randomized block experiment with four replications having split-plots which were cut at 6-, 8-, and 12-weekly intervals. The grasses were planted vegetatively at a uniform spacing 21 months before treatments commenced. Treatments were continued for two years, during which all plots received a mixed fertilizer application every six weeks totalling 8 cwt an acre urea, 4 cwt an acre superphosphate, and 2 cwt an acre potassium sulphate a year ; this was in addition to liberal fertilizer applications during the establishment period. Rainfall was supplemented with irrigation. The introduced grasses differed markedly in total annual yield of dry matter, persistence, seasonal growth rate, reaction to cutting frequency, frost susceptibility, and amount of weed invasion, and it is concluded that a number of them are potentially much superior to naturalized P. dilatatum as pasture grasses in south-east Queensland. The best grasses were P. yaguaronense (C.P.I. 11867), P. notatum var. saureae (C.P.I. 9073), P. notatum var. latiflorum (C.P.I. 11863), and P. plicatulum sens. lat. (C.P.I. 2741) ; these all produced annual yields at 6-weekly cutting of over 17,000 lb an acre dry matter and had a much better seasonal distribution of production than naturalized P. dilatatum. Six other grasses also appeared to be superior to naturalized P. dilatatum. They are P. dilatatum var. pauciciliatum (C.P.I. 11814, 11824, 11859), P. conspersum (C.P.I. 17651), P. urvillei (C.P.I. 11868), and P. plicatulum var. glabrum (C.P.I. 11826).