New Saltland Grazing Options in Major Trials at Kangaroo Island

_This project is now complete. For further information go to the [Sustainable Grazing on Saline Lands](http://landwaterwool.gov.au/index.php?q=subprogram/6) section_.

Maximising the productivity of saline and waterlogged country is the focus of two new farmer-driven research projects on Kangaroo Island.

The projects focus on rotational grazing and raised bed plantings of saltland pastures.

The Kangaroo Island Soil Conservation Board is behind the SGSL rotational grazing project, which is being conducted on the property of group member Malcolm Schaefer. The property lies on the south coast of the island between Lake Ada and Murray Lagoon, a 550 mm rainfall one-time lake bed property.

Project Leader for SGSL, Jock McFarlane, said the research is aiming to further fine tune management of pasture production on salted and waterlogged land.

“With approximately 10,000 ha of saline land on Kangaroo Island, there has been a huge effort to overcome the problem by local landholders,” he said. “Over the past 20 years, awareness of how to manage salinity has increased greatly.

“Now farmers know the basics, they want to fine tune the system to make the saltland pastures more productive, to further increase water use, while also ensuring the system is sustainable.”

Jock said the findings from Malcolm’s project are extremely important in the context of South Australia’s useage of puccinellia and wheat grass. “These plants form the basis of South Australia’s saltland agronomy representing an area of approximately 250,000 hectares,” he said.

With 242 ha of Malcolm’s property so salted that it only produced barley grass through the 1980s, improving production on these areas has long been a priority of his.

Over the past ten years, Malcolm has gradually established tall wheat grass and puccinellia pastures with great success.

“The puccinellia-tall wheat grass pastures are now a valuable part of our grazing system, providing good summer feed and good early feed at the break of the season,” he said.

“Now I want to know whether or not rotational or cell grazing will enable us to graze these pastures for 12 months of the year.

“If the system works, it will not only increase our productivity, but will also increase water use which will benefit the saltlands.”

Project support officer, Lyn Dohle from SA Rural Solutions, said the SGSL trial was established in August last year on a two-year-old stand of puccinellia and tall wheat grass, and includes an eight cell system, with paddocks around 2.4 ha each.

“One paddock is set stocked at 6 DSE/ha, and one paddock is managed on an “ad-hoc” system. The remaining paddocks are rotationally grazed, also working on 6 DSE/ha/per year,” she said.

“The grazing time in the rotation will vary from three days during maximum pasture growth, out to 10 days when the season dries off. Records of pasture height and sheep weights are being taken as sheep move from cell to cell. Pasture composition will be assessed every six months.”

While it’s too early at this stage for any conclusive trial results, Malcolm said he’s been very impressed with the rejuvenation of the tall wheat grass after seven weeks of de-stocking during the rotational grazing system.

“Quick rejuvenation is an obvious advantage, because good surface cover will reduce evaporation, which brings salt to the surface,” he said.

“However, we need time to see whether the pasture gets too rank under rotational grazing, or if the sheep go backwards.

“After a year we should have an idea of whether it is sustainable or not.”

Nitrogen application on saltland pastures is also part of the project, with both autumn and spring applications to be trialed.

A raised bed pasture project will fire up this year, with the beds to be formed in March/April.

Lyn said the three research sites will be on properties in the SouthWest, Bugga Bugga/Timber Creek and Eleanor/Lake Ada catchment areas.

“We want to know if raised beds have a place in salt land management, whether the returns will justify the cost of putting in the beds and how practical the system will be,” she said.

Lyn said the concept works well in a cropping regime and now is the time to try it in a saltland agronomy situation.

“A lot of salt areas also get very wet – plants tend to be able to survive either salt or waterlogging, but not both,” she said. “By putting in raised beds, we’re reducing the waterlogging stress, providing a more hospitable environment for the pasture.”

However, the day-to-day management of the flocks and impact of livestock on the bed formation are issues that need to be researched, as well as determining if the raised beds improve productivity sufficiently enough to justify the cost.

Pastures to be planted on the beds will include the traditional Kangaroo Island salt-land pasture mix of puccinellia, tall wheat grass and strawberry cover, as well as a conventional pasture (which may be lucerne, phalaris or ryegrass) as well as summer-active tropical grasses such as Rhodes grass.

Malcolm said he is taking a lot of interest in the projects being run by other SGSL groups.

“The program provides an opportunity to learn from other producers, particular those in areas with similar rainfall and site characteristics,” he said.

First published April 2004. For more information go to the Sustainable Grazing on Saline Lands Sub-program.