Self-Help Ethos Attracts Saltland Research to Tammin

This project is now complete.

FOR most of the 1990s, saltbush was regarded by many as worthless for sheep feed, even though it was one of the few plants able to tolerate high levels of salt. But Tammin farmer and wool grower Tony York was one of a small band who believed it was part of the solution to living with salinity and continued to plant it.

This ‘self-help’ ethos among a group of local WA wheatbelt farmers has led to Tammin recently becoming an important Land, Water & Wool Sustainable Grazing on Saline Lands (SGSL) site.

Project manager Robyn Dynes from CSIRO Livestock Industries said enthusiastic support from the Saltland Pastures Association and in particular, Tony York and his family had made Tammin the location for research into the economics of saltbush on farms.

“Being east of Meckering, Tammin is genuine dryland country,” Dr Dynes said. “There’s also a high risk of the salinity increasing over the coming decades, plus a thriving Landcare centre that attracts teachers and school groups.”

The property also had large plantings of saltbush, giving researchers a head start in studying its feeding value and economics. “About a fifth of our 10,000 hectare property is affected by salt,” Tony said. “Twenty years ago I brought in bluebush to try and maintain some growth on the saline areas.

“This grew quite well, but after 10 years it became clear that the bluebush was failing to colonise the more saline sites. Then we tried saltbush, mainly old man saltbush (Atriplex nummalaria).”

The Yorks have owned their property for three generations but for the past 40 years no-one had tried to grow crop on what is now the main SGSL research site because of encroaching dryland salinity.

However in recent times the saltbush has provided six-to-eight weeks of valuable autumn grazing when little else was left standing. But while man cannot live on bread alone, neither can sheep live only on saltbush. Without other pasture or supplements such as hay, it contains too much salt and insufficient energy.

Combining saltbush with more digestible understorey plants is one key to successful saltland pasture, and establishing which varieties work best is an essential part of the research.

Robyn Dynes said about seven understorey varieties were being tested at Tammin including Balansa and Persian clovers. So far, there is no clear winner, as species appear to be finding their own preferred environment depending on the salinity and acidity of the soil.

While saltbush has been grazed for decades, comparatively little is known about it. The scientists are still not sure whether the saltbush is driving down the water tables or just drying out the soil and making life easier for the understorey.

“There is very little information out there about how much water saltbush uses, for example,” Robyn said. “This work will provide important information, not just for the WA wheatbelt but for many other areas across Australia where saltbush is used for grazing.”

The year 2003 has been the second year of research on the York property, which has been much more benign than 2002 when only about 90 mm of rainfall fell. Between now and 2006, variation in seasons should help provide important information on saltbush’s place in the farming system.

Filling the autumn feed gap for sheep is a good reason to grow saltbush in WA, but it needs to be combined with tastier annual clovers and other species for best results.

“The Yorks have provided a huge commitment to this research in both use of land and sheep,” she added. “Tony is always happy to speak to people and to fit in with the research, even when we wanted to remove some of his saltbush to see how that affected production.”

Besides assessing the feeding value of saltbush for sheep and wool production, scientists are planting new saltbush and taking part in a national trial to compare salinity tolerance of a wide variety of legumes and grasses.

First published November 2003. For more information go to the Sustainable Grazing on Saline Lands Sub-program.