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In southern New South Wales, Australia, grazing wheat during the vegetative and early reproductive growth stages (typically during winter) can provide a valuable contribution of high quality feed during a period of low pasture growth. This paper reports results from a series of experiments investigating the agronomic management of grazed wheats in southern NSW. The effect of sowing date and grazing on dry matter production and subsequent grain yield of a range of wheat cultivars was measured in five experiments in 2004 and 2005. In all experiments, results were compared with ungrazed spring wheat (cv. Diamondbird). Grain yield of the best winter cultivar was either the same or significantly greater than the spring cultivar in each of the five experiments. Within the winter wheat cultivars, there was significant variation in grain yield, protein content and screenings, depending on site and year with the cultivar Marombi out-yielding all others. Interestingly, this cultivar usually had the least dry matter post-grazing but the greatest dry matter by anthesis of the winter wheats. Generally, if sowing of the winter wheat was delayed, then the effects on yield were small or non-existent. The results are discussed with respect to the benefits of incorporating grazing cereals into cropping programs in the medium rainfall zone of southern Australia. [ABSTRACT FROM AUTHOR]

A collaborative project between researchers, regional natural resource management organisations and landholders set out to explore three questions about the relationships between biodiversity and land use in Australia's mixed-farming landscapes: (1) the extent to which farm-scale measures of biodiversity were related to agricultural production; (2) the influence of the type and intensity of agricultural production on native biodiversity on farms; and (3) the relative influence of site and farming system on selected measures of biodiversity. Four land-use types on 47 mixed farms across nine regions, derived from several of Australia's 56 natural resource management regions, were surveyed in autumn and spring 2006 and 2007. Surveys of birds, surface invertebrates (beetles, ants, spiders), vegetation and soils were undertaken on four land classes on each farm; crop, 'rotation' (break crop/pasture phase), perennial pasture and remnant vegetation. Data were collected by participating regional staff, using a standard protocol, which were sent to a central collection point for collation, analysis and interpretation. Species richness, functional diversity and vegetation structure were assessed. This introductory paper focuses on results relating to species richness, which for most taxa was greater in remnant vegetation than other land-use classes and declined along a disturbance gradient (remnant, pasture, rotation, crop). Properties with a greater proportion of perennial pastures recorded higher species richness than properties that were dominated by crop. Properties that recorded high wheat yields (t/ha) also recorded lower species richness for spiders and birds. The presence of insectivorous birds and beneficial invertebrates (spiders, beetles and ants) in all land-use classes suggests the potential to apply integrated pest management approaches to mixed-farming systems across the country. Site and system features were found to be important determinants of biodiversity, with their relative importance varying with the scale of investigation and the taxa. At the landscape scale, bird species richness was correlated with the amount of remnant vegetation within a 5-km radius of the farm boundary, and with the condition of native vegetation on the farm. The average size of remnant vegetation patches was 5 ha or less on nearly half of the properties surveyed. At the farm scale, ant species richness was correlated with site features, while beetles were correlated with management/system features such as the presence and fertility of perennial pastures. Analyses at the functional group level will provide more detailed information on relationships between different land-use types. Further experimental work needs to be undertaken to qualify the suggested impact of land management practices on different taxa, while repeated surveys will allow for the collation of datasets over time, from which population dynamics may be determined. [ABSTRACT FROM AUTHOR]

Limited information is available on the management and delivery of national-scale biodiversity projects. Even less information is available on such projects operating in agricultural matrices, particularly how they address the expectations of multiple stakeholders from paddock to farm, regional and national scales. This paper describes the approach taken to implement and deliver the Biodiversity in Grain & Graze project, which was national in focus, regional in operation and local in delivery. The project was instigated by four research and development corporation partners who were keen to connect the interests of mixed-farming producers to the environmental goals of nine collaborating regions across Australia. One aim of the project was to engage producers in participatory research on the biodiversity values of mixed-farming systems. This aim could not have been met without considerable effort building regional capacity in biodiversity research and developing a national network of researchers, regional extension staff and stakeholders. This national network was engaged primarily through program and project workshops, regular electronic communications and site visits. Levels of engagement were high, resulting in a sense of ownership by all stakeholders, counteracting to some degree the ill feeling associated with the late inclusion of the biodiversity project to regional activities. Issues relating to goal confusion were evident throughout the whole project, despite a concerted effort by the project team to address such tensions. Previous studies have indicated, and we concur, that biodiversity components need to be built into programs like Grain & Graze at the beginning, and need to be developed in consultation with farmers, regional agencies and research organisations to ensure that expectations are shared and the project is fully supported. [ABSTRACT FROM AUTHOR]

The 'Regional Combinations' project and its biophysical outcomes have been described in several other papers in this special edition. The information provided in these papers allows an evaluation of the most profitable beef cattle production systems across different environments in southern Australia. In this paper, the focus is on the New South Wales experimental site where the trial animals were finished in a feedlot. The data identified liveweight gain as the biggest driver of profitability of production. Between growth treatments, there was a large difference in the gross margins before feedlot entry between the 'fast' and 'slow' treatments favouring the fast-grown animals, even after accounting for the higher cost of producing pasture capable of sustaining faster growth. However, the slow growth treatments consistently outperformed the fast growth treatments in the feedlot. In terms of breeds, the European breed types consistently outperformed the Wagyu breeds. There were no time-of-calving experiments in New South Wales. [ABSTRACT FROM AUTHOR]

The 'Regional Combinations' project and its biophysical outcomes, and the subsequent identification of the most profitable beef cattle production systems across different environments in southern Australia, have been described in several other papers in this special edition. In this paper, the economic calculations reported for each of the individual beef enterprises representative of the various state sites are aggregated up to the level of the Australian cattle and beef industry and then projected forward over several years into the future. To do this, an existing model of the world beef market is used. The analyses suggest that both the fast-growth-rate technology and the time-of-calving technology have the potential to generate significant economic benefits for the southern Australia cattle and beef industries. The cumulative present values of each technology are around $70 million over a 15-year time horizon at a 7% real discount rate. [ABSTRACT FROM AUTHOR]