[Comment: introduction here]

Western Australia's farming systems are a legacy of the 'sub and super' revolution that allowed development of millions of hectares of nutrient deficient, light land soils cleared for agriculture in the 1950s, 1960s and 1970s. Superphosphate and trace elements allowed the prolific growth of subterranean clover for animal production and provided the residual nitrogen needed to grow the following cereal crops.

Many challenges to this simple system - phyto-oestrogens (clover disease), poor seed set, inadequate hard seed, insect pests and fungal disease - have been met and overcome through scientific research in the decades since the system was introduced. More recently, low prices for wool and animal products have reduced producer interest in improving pastures for animal production, but wool prices are rebounding and new opportunities to use pastures as vital parts of sustainable crop-orientated farming systems are emerging. Development of new pasture species with improved adaptation to hostile soil conditions, aerial seeding for easy harvest and short pasture phases are poised to recapture a significant role in farming systems.

• Cultivars