The paper reports the outcomes of two on-farm experiments that aimed to identify the most cost-effective strategies to control herbicide-resistant annual ryegrass in rainfed, no-till, wheat-based farming systems in southern NSW. The studies linked efficacy of annual ryegrass control with the relative profitability of combinations of different crop sequences and agronomic management. The results showed that three consecutive years of >95% weed control by using diverse crops are required to cost-effectively reduce annual ryegrass seedbanks in soil to manageable levels.

The production of edible dry matter (EDM) of 2-year-old tagasaste shrubs averaged 2.7 kg shrub⁻¹ year⁻¹ on one steep, north-facing hillside on the eastern coast of New Zealand. This equated to the production of 2.2 t EDM ha⁻¹ year⁻¹ at spacings of 3.5 m (816 shrubs ha⁻¹), with a metabolisable energy content averaging 10.0 MJ kg EDM⁻¹. In low-producing (<4 t DM ha⁻¹ year⁻¹) pastures on drought-prone, steep-hill country, inclusion of tagasaste could increase edible forage production by 50%.

Barley grass is an invasive weed in southern Australia, with sharp seeds that can penetrate the flesh of grazing sheep, affecting production and animal welfare. Using a simulation modelling approach, this study compared the efficacy of single versus combined weed management strategies on barley grass populations within a lucerne pasture over 10 years. Combined control practices were found superior for reducing seed production, and the reported approach will enable the selection of optimal control strategies for reducing impacts on livestock production.

There are strong ethical, environmental, and economic reasons for increasing the phosphate-use efficiency of white clover, a natural hybrid between Trifolium pallescens and T. occidentale. White clover has poor phosphate-use efficiency, but we found significant variation for relevant characteristics between the two parental species and among populations within each species. Developing cultivars using superior populations of the parental species could be a very effective breeding strategy for increasing phosphate-use efficiency of white clover.