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Approximately 3.1 Mha (22%) of the agricultural area of south-eastern Australia can be classified as native pasture. There is the assumption that, owing to the widespread occurrence of low-fertility soils in Australia, native grass species do not respond to increased phosphorus (P) fertility. Currently, there are no industry recommendations of target soil-test P values for native-grass-based pastures. This paper reviews the responses of perennial native pasture species endemic to south-eastern Australia to P application in controlled environments, surveys, replicated experiments and paired-paddock trials. Eighty-seven site-years of trial data where different levels of P were applied, conducted over the last two decades, on native-based pastures in south-eastern Australia are reviewed. Data indicate that application of P fertilisers to native grass pastures can increase dry matter (DM) production and maintain pasture stability. However, minimum targets for herbage mass (800 kg DM/ha) and groundcover (80%) are required to ensure persistence of perennial native grasses. Stocking rates also need to match carrying capacity of the pasture. Based on previous research, we recommend target soil-test (Olsen; 0–10 cm) P levels for fertility-tolerant native grass pastures, based on Microlaena stipoides, Rytidosperma caespitosum, R. fulvum, R. richardsonii, R. duttonianum and R. racemosum, of 10–13 mg/kg, whereas for pastures based on fertility-intolerant species such as Themeda triandra, lower levels of

Temperate pastures that leak water below the root zone have been linked to an increase in dryland salinity in southern Australia through their conservative use of stored water. An experiment was conducted at Hamilton in south-western Victoria to test the hypothesis that deep-rooted, summer-active perennial pasture species can substantially reduce leakage. On topographic crests the experiment compared lucerne and chicory with a traditional perennial ryegrass variety with low summer activity, whereas on the poorly drained valleys the comparison was between tall fescue, kikuyu and a perennial ryegrass variety with high summer activity. Lucerne developed a buffer of dry soil to a depth of at least 5 m. An empirical relationship with June–September rainfall indicated that with this dry buffer, leakage below the root zone would not occur even in the wettest of years. Chicory developed a dry buffer to the depth of measurement (3 m), but plant density gradually declined and leakage started to occur 5 years after sowing. The perennial ryegrass with low summer activity had leakage nearly every year. On the valleys kikuyu was initially the most effective at drying the soil in summer, but its density declined at the expense of annuals and 3 years after sowing it became wetter than the other treatments. None of the pasture options on the valley fully controlled leakage, but both the summer-active perennial ryegrass and tall fescue were persistent and there was little difference in their capacity to extract summer moisture. This study showed that four characteristics were associated with a pasture that controlled leakage – summer activity, persistence, adequate density and deep rootedness. Of the species tested only lucerne satisfied all these criteria.