Development of a rainfed lucerne-based farming system in the Mediterranean climatic region of southwestern Australia

In the southern coastal region of southwestern Australia with a Mediterranean-type climate, rising water tables prompted the owner of the farm, ‘Laurinya’, near Jacup, Western Australia (34°S, 119°E), to extend small plantings of lucerne near saline streams to large areas of the farm. In recent years, the area under lucerne has increased from 20 to 800 ha. The aim is to ultimately have all pasture on the property as lucerne-based perennial pastures. The lucerne is sown with a no-till seeder in rows 250 mm apart. In two contiguous rows in every five rows, barley is sown with the lucerne to provide protection to the young lucerne plants from sand particles carried by high winds in the sandy-surfaced soils of the region. The barley also provides an income stream in the year of establishment of the lucerne. The lucerne-based pastures are the foundation of a phase-farming system. A period of lucerne varying in length from 2 to 10 years is followed by a cropping phase of 3–10 years. The lucerne pastures are rotationally grazed for 1–2 weeks with 5–6 weeks between grazing. The lucerne provides nitrogen to subsequent crops and assists with the control of volunteer grasses and summer weeds. It also uses water that otherwise would leak past the root zone and lead to rising water tables and secondary salinity.