Less publicly, the region's dairy industry has also recognised the value of this summer legume option.

Soybeans have been a key element in the summer feed program of the Casino dairy farm of Sam and Fleur Tonge and manager Paul Judge for a number of years.

The Tonges and Judge, who supply Parmalat, aim to supply milk at a constant level throughout the whole year.

"The strength of the farm is its ability to produce feed from a pasture based system," Judge said.

"We have a good and reliable water allocation from Toonumbar Dam, west of Kyogle, so, in general, dry times are manageable.

"However the most difficult times are either in extreme wet weather or extremely hot weather, when it is very difficult to satisfactorily feed the cows solely on pasture.

"This is when the silage becomes very important."

Judge said while the farm can harvest a significant amount of its silage needs from the winter pastures, he and the Tonges are very pleased with the quality of the soybean silage that they make in summer.

The aim is to make about 800 round bales, which should provide reasonable feed security for the next year.

Soybeans had proved a useful summer legume in the crop rotation, but there had been problems with cow peas and Dolichos lablab through diseases associated with heavy clay soils and wet summers.

The soybeans seemed to be more tolerant to diseases but are perhaps more difficult to establish at planting time.

According to Tonge, Judge has developed a reputation for his abilities with record keeping and on-farm feed budgeting.

"That reputation, coupled with the history of the farm, prompted NSW Department Primary Industries and BGA Agriservices to base a trial here to test a new variety of soybeans developed by the Australian Soybean Breeding program in a commercial dairy situation," Tonge said.

The Australian Soybean Breeding program is funded by the Grains Research and Development Corporation (GRDC), CSIRO and NSW DPI, with the actual trial developed and completed by Dr Natalie Moore from NSW DPI, Grafton, in association with BGA Agriservices agronomists Mark Carter and Dominic Hogg.

The trial compared the new variety Hayman and the most commonly used variety for silage production on the NSW North Coast, Asgrow A6785.

Crop establishment was into a chemically prepared seedbed using a precision planter.

Weed and insect control regimes were similar for both varieties and were in keeping with standard industry practices.

The crops were cut for silage in March and were made into round bales.

The key observations and conclusions from the trial were:

Hayman produce a lot more biomass – 11tonnes of shoot dry matter/ha compared to 8.7 tonnes shoot dry matter/ha by A6785 grown under the same conditions and harvested at the same stage of maturity, mid pod fill.

Hayman matured more slowly at the end of the season than the currently available grain types of soybean, allowing an extra 10-14 days for hay and silage making compared to A6785. (This is beneficial in coastal areas like the NSW north coast, where wet weather can delay operations.)

Feed value analysis of hay and silage showed that Hayman's nutritional values were similar to A6785 and acceptable for dairy silage.

Although producing more biomass and being taller than A6785, Hayman has less tendency to lodge, an important trait in the NSW north coast climate.

Due to the late maturing characteristic in this environment, and its excellent grain quality (clear hilum, large seed size and high protein) Hayman will likely have a secondary role as a grain variety for very late sowing dates in the region.

Hayman seed is expected to be commercially available for the summer plantings in 2012/13.

Judge said, as with most things in dairying, the cows are testing critics of the quality of feed and he is pleased with how the herd has eaten the Hayman soybean silage.

"Having a contractor chop the crop in the bales has improved the dry matter intake for the cows," he said.

"The herd has coped well with the hot weather and I believe that the Hayman variety is an appropriate choice for us to use in our summer silage program.

"I am very keen to try it in a grazing situation once seed is commercially available. I suspect that the taller plant and slower maturity will be advantages.

"Hayman's harvest time works in well with having our ground ready for ryegrass in late March. It is a crop that fits neatly into our feeding system."