Multi-species cover cropping trials in northern New South Wales are underway to see if the practice can build stored soil moisture and improve soil health.

AMPS Research is conducting the trials under new research chair Tom Simson, who is excited about the trial's prospects.

A changing of the guard occurred earlier this year for the group, with well-known northern grower and research advocate Gordon Brownhill handing over the research chairmanship role to Tom.

Along with his parents Ed and Fiona, Tom runs a 5800 hectare mixed farming operation on the western side of the Tamarang Mountain, east of Coonabarabran.

Although he was in primary school when an innovative group of northern NSW growers decided to invest in localised research and form AMPS two decades ago, Tom says the original vision for local, versatile research still holds strong.

"Agriculture is forever changing and we have to be able to adapt quickly to suit what's happening, whether it be climate, herbicide resistance, emerging varieties, social trends, technologies ... the list is endless," he says.

"If we as the producer can't meet those demands or standards, then we will quickly fall behind. That's why I believe valid research is vital to agriculture."

Cover cropping

Although the concept of cover cropping is not new, for many in the area, including Tom, planting a multi-species cover crop is. For this reason, Tom is keenly watching the results.

"I believe there is a lot of merit behind it. Globally, many farms are benefiting from the practice," he says.

After discussing the idea with AMPS researchers Matt Gardner and Scott Bennett, within a few weeks a trial concept was developed.

Gordon Brownhill, right, has handed over the research chairmanship role at AMPS Research to Tom Simson, left. Photo: Supplied

"AMPS' ability to respond to research questions is timely. It doesn't get better than that," Tom says.

The trial at 'The Plantation' will run over the next three years and will see a blend of oats, rye corn, tillage radish, faba beans and field peas used to grow ground cover.

The species and number used may change over time depending on which crops perform well. The team is also testing each species individually to see which add the most value in bulk and nutrition.

Soil testing was undertaken before sowing and will be done again once the plot is sprayed out. Sorghum will then be sown on the plots to assess productivity.

Depending on this year's results, next year may see the cover crops grown for longer, before being grazed. The benefits that cattle urine and manure have on the soil could also be tested.

Tom says improved soil health and water infiltration are very important trial outcomes.

"Multi-species cover cropping seems like a great idea and overseas examples show that," he says.

"But we need to remember that some of the places where it works - like parts of the US - get over a foot of snow each year.

"Our circumstances are completely different. We have the scope to make it work but we need to test it."

Other R&D areas

AMPS will also continue its research into time of sowing, which was initiated to investigate the impact of elevation on frost risk and what this could mean for sowing dates on land with different elevations.

For the past five years, AMPS, with GRDC support, has undertaken these trials, three of which have been at the Simsons' farm. Tom says the trials have played a major role in changing his family's winter cropping program.

"The trials have found that delaying planting past the last week of April gives us a loss of 40 kilograms, per hectare, per day," he says.

"This number has moved our planting date forward from the last week of May. Instead, this year we kicked off on 8 April."

The Simsons still mitigate risk across the cropping program by splitting up dates, varieties and elevation where possible. The benefits, for them, include establishing a crop before really cold weather hits and flowering in September, rather than October's often-extreme heat.

"In 2014 we saw a week of 40°C-plus weather in mid October," Tom says.

"We had a pretty handy-looking crop that year, which was mid-flower. I'd hate to know how much grain was lost."

Understanding temperature

The trials have also helped Tom and AMPS Research gain a better understanding of temperature at varying elevations. For example, in 2017 at the bottom of a slope (390 metres above sea level), they recorded 92 events below 0°C, with a total of 543 hours. However, at the top (431m), 34 0°C events were recorded, for 112 hours.

"The difference equals 16 days below O°C," Tom says.

He says the family's paddocks have been designed to run up or down the hill for efficient machinery use, a practice that will remain. However, the temperature and elevation results have led to another trial - a variable seeding one using a 'split bin'.

The idea is to draw an 'elevation line' in the paddock and switch varieties to suit the temperature faced.

"We'll put an earlier variety up the top to maximise yield and a slower variety down the bottom to compensate for the cold," Tom says.

Legacy

Tom, who graduated from Marcus Oldham College and worked for the Consolidated Pastoral Company before coming back to the farm, is looking forward to continuing Gordon's legacy.

"The best thing about AMPS is our reliable, factual, localised data; data that has come from a grower's area and is logical for their business, environment and situation," he says.

"A priority of mine is to carry on with this, to keep our research versatile and growers engaged."

He says growers often come in with research ideas and AMPS wants to continue to encourage that.

"Last year we saw a linseed trial go in at Gurley at a grower's request," he says.

"Then an Armatree grower wanted the same trial at his place. I feel privileged to have these growers in our group because these factors drive an industry forward.

"I want to continue encouraging engagement and ideas from our growers to make sure the trials stay relevant.

"Now I've taken the reins my priority is to build on Gordon's legacy and achieve results."

More Information: Tom Simson, tomsimson8@gmail.com; AMPS Agribusiness