Snapshot
Growers: Craig and Fiona Marshall, with their children Daniel, Meghan and Samuel; and employees Andrew Simons and James Halliwell
Farm location: Rennie, NSW
Area cropped: 3150 hectares
Rainfall: 450 millimetres (long-term annual mean); 582mm (1 January to 7 December 2021)
Soil types: red loam, sand and grey clay
Topography: flat
Soil pH: less than 5.0 to 5.0 (calcium chloride)
Enterprises: 90 per cent cropping; 10 per cent sheep
Crops grown: LRPB Trojan, LRPB Kittyhawk and Scepter wheat; 45Y94 CL, 45Y23 RR, 45Y28 RR canola; 45Y29 RR canola; HyTTec® Trophy; RGT Planet and La Trobe barley
Typical crop sequence: canola/wheat/barley
A steadfast focus on continuous improvement has earned the Marshall family a prominent agronomy award.
Craig and Fiona Marshall, who crop 3150 hectares near Rennie in southern New South Wales, were the winners of a 2020 GRDC Hyper Yielding Crops (HYC) award.
The award was issued through GRDC’s HYC initiative, led by Field Applied Research (FAR) Australia, which aims to close the gap on potentially achievable yields.
GRDC’s HYC awards program aims to encourage growers with an interest in lifting yields to submit one wheat paddock for agronomic benchmarking.
GRDC Southern Panel member and HYC extension lead Jon Midwood, of TechCrop Services, announced Craig and Fiona Marshall as winners of the 2020 ‘Highest Percentage of Potential Yield’ in NSW.
“The Marshalls achieved this accolade with 164 hectares of Scepter wheat, which yielded 6.71 tonnes/ha of grain,” Mr Midwood says.
“The crop yielded 86.36 per cent of the paddock’s biophysical potential grain yield, which was estimated at 7.77t/ha. The potential yield was calculated with a model that accounted for plant-available water to a depth of one metre, in-season rainfall, temperature and radiation.”
Craig says he was pleased to discover the family’s 2020 HYC award paddock ‘Pine Hills’ had the capacity to produce a higher yield than it actually did.
“Our first year in the HYC awards program showed we have the capacity to push our wheat harder than we have previously, particularly in seasons with above-average rainfall,” he says.
The Marshalls first heard about the HYC awards through Fiona’s involvement as a board member of Riverine Plains, an independent farming systems group headquartered at Mulwala.
After Craig and Fiona submitted a paddock for HYC agronomic benchmarking through the program, Riverine Plains project officer Kate Coffey visited the Marshall family’s farm during 2020 to gather information.
“Farming is Craig’s hobby as well as his job, and he really loves having a paddock to focus on to see if he can push our wheat crops harder,” Fiona says.
“We have found it interesting to work with our Elders agronomist Matt Coffey to set up our awards paddock and, at the end of the season, compare Craig’s agronomic management with others.”
Management insights
Late summer and autumn rainfall during 2020 at the Marshalls’ awards paddock ‘Pine Hills’ was well above average, which produced excellent sowing conditions.
Pre-emergence grasses were targeted with 118 grams/ha of pyroxasulfone (Sakura® 840 WDG) and incorporated by sowing.
The 2020 awards paddock was sown on 12 May with a tyne and press wheel seeding rig set on 250-millimetre row spacings.
The seed – treated with 200 millilitres per 100 kilograms of Hombre® Ultra (imidacloprid and tebuconazole) – was direct-drilled at 80kg/ha into a canola stubble that had been grazed by sheep during the 2019-20 summer-autumn break.
Starter fertiliser in the form of monoammonium phosphate (MAP) – 8N, 18P and 2S – was applied with the seed at 80kg/ha.
The HYC awards project uses climate data from the SILO website. This relies on mathematical interpolation techniques using ground-based weather data to provide a database of Australian climate data from 1889 to the present.
Data from SILO is used to determine growing season rainfall, temperature, radiation and plant-available water capacity to a depth of one metre. This is then used to estimate the biophysical yield potential of each award paddock.
Overall, 2020 rainfall at the Marshalls’ ‘Pine Hills’ paddock was above average, a complete contrast to 2018 and 2019, which were both dry.
With a full profile coming into winter, June and July 2020 turned dry, enabling the family to apply nitrogen, herbicide and fungicide.
On 5 June 2020, 100kg/ha of urea (46N) was spread on to the growing Scepter crop.
In-crop weeds were targeted on 8 July with 0.75 litres/ha of Tigrex® (MCPA ester and diflufenican).
On 5 August ahead of a rain front, Craig spread a further 100kg/ha of urea (46N), taking the total nitrogen applied to 100kg/ha.
When the crop reached growth stage 31 on 28 August 2020, a 0.5L/ha treatment of Opus® 125 (epoxiconazole) fungicide was applied to protect against disease.
Spring rainfall during 2020 at the award paddock cut out after October.
The 2020 award paddock was harvested on 15 December. Weighbridge tickets sent to Ms Coffey confirmed a 6.71t/ha yield.
Benchmarking outcomes
In early 2021, Mr Midwood and the HYC team analysed data from the 65 growers Australia-wide who took part in the first year of the HYC program.
Then, reports were sent to all program participants. Histograms were used to accumulate and interpret datasets and to keep individual data confidential.
“The commentary in each report allows the agronomy decisions of participating businesses to be compared,” Mr Midwood says. “We note the figures for the top 20 per cent of paddocks, the average and then describe where each participant sits in relation to others.”
The Marshalls earned their award because the yield of their Scepter wheat crop on the ‘Pine Hills’ paddock ranked the highest in NSW when expressed as a percentage of its biophysical yield potential.
Soil analysis
One issue mentioned in the Marshalls’ HYC agronomic benchmarking report was that topsoil pH in ‘Pine Hills’ was low at 5.0.
Craig and Fiona are aware of the impact of acid soils on crop performance and have developed a comprehensive plan to remedy the issue using variable-rate lime.
Their long-term aim is to lift topsoil pH to at least 5.2 to ensure nutrient availability is not limited, while being high enough to ensure aluminium toxicity is not an issue.
Topsoil phosphorus, potassium, sulfur and organic carbon in the focus paddock were above critical values.
Another potential ‘tweak’ noted was the capacity to lift yield by increasing total nitrogen.
According to the report, 100kg/ha of nitrogen was supplied to the Marshalls’ Scepter wheat on ‘Pine Hills’ during 2020.
However, the top 20 per cent of HYC awards paddocks in NSW had a total nitrogen supply of 171kg/ha on average. This was significantly higher than the 113.6kg/ha of total nitrogen applied, on average, to all NSW HYC award paddocks during 2020.
Lessons learned
After finding the 2020 results a fascinating insight into the impact of agronomic management on grain yields, the Marshalls entered another paddock into the 2021 HYC program.
Their 2021 award paddock was an ungrazed crop of LRPB Kittyhawk wheat sown into canola residue during April.
To see whether grain yields could be pushed higher, and after consulting with their agronomist Matt Coffey, they significantly increased the total nitrogen applied.
“Normally, for wheat we apply 80kg/ha of MAP, but we increased that to 90kg/ha,” Craig says.
“We generally only apply 200kg/ha of urea to our wheat, but the total amount of urea added to the LRPB Kittyhawk wheat on our 2021 HYC award paddock was increased to 320kg/ha.”
When GroundCover™ visited the Marshalls’ farm during early November, the LRPB Kittyhawk wheat on the award paddock was still green and filling grain on the back of above-average rainfall and a mild spring.
“Watching the LRPB Kittyhawk change on a daily basis into a high-yielding wheat crop lifts our spirits,” Fiona says. “Seeing it grow and improve every day is inspiring.”
Business improvement
Aside from agronomic benchmarking, the Marshall family also puts business performance under the microscope on a regular basis through a not-for-profit farmer-run business called Ag Edge.
The program allows Fiona and Craig and the directors of five other mixed-farming businesses from southern Queensland to southern Victoria to act as an independent advisory board for each of the six businesses.
“At a two-day meeting, for example, we might have two hours to concentrate on our business concerns with the other members of the board,” Fiona says.
“It also allows us to have an intimate knowledge of how five other farming businesses operate and this is a fantastic learning opportunity.
“Together we interrogate issues, offer suggestions to solve any issues others raise and seek feedback on progress dealing with our issues.
“It is enormously valuable to have 12 people bringing their knowledge and experience to the table to discuss our business, offer ideas, raise issues and keep us accountable.”
The Marshalls have also engaged agricultural consultancy business Agripath for business planning, benchmarking and reviewing their business.
The services delivered by Agripath consultants Jasmine Whitten and Simon Fritsch help them set goals, implement change and review performance year on year with the aim of consistent incremental improvement.
Carbon benchmarks
Another way Craig and Fiona have embraced continuous improvement within their grains business is through their participation in the Cool Soil Initiative.
The initiative is a Food Agility Cooperative Research Centre project that brings together growers, farming systems groups, Charles Sturt University, Mars Petcare, the Manildra Group and Kellogg’s Australia.
The project is investigating management practices that mitigate greenhouse gas emissions to ensure the sustainability and profitability of NSW farming enterprises. Craig and Fiona’s business is one of about 100 engaged in the program, which draws on science-backed analysis from independent soil scientist Dr Cassandra Schefe of AgriSci.
“International soil carbon targets are unrealistic for Australia because of our ancient and weathered soils, so Dr Schefe, through the initiative, is working with us to benchmark our soils and develop realistic and relevant targets,” Fiona says.
Specifically, soil carbon is measured at the same location every time wheat is grown in the Marshalls’ cropping sequence. Over time, soil carbon levels will be compared to determine the trend.
Improving paddock nutrient status is critical for Craig and Fiona Marshall, who farm mostly red loam soils. Photo: Rob Lacey
One strategy embraced to boost soil carbon on the Marshalls’ farm is to apply composted animal manure.
Craig and Fiona seek grain marketing contracts with local feedlots with the aim of backloading composted manure for spreading across their paddocks.
With the price of urea almost tripling in the past year, Craig says the family might need to take a closer look at the place of pulse crops and pasture legumes in their rotation.
“If the price of urea continues to remain high, we may need to reassess the merits of adding an extra break crop like faba beans into our cropping sequence,” he says.
“If we can’t grow faba beans because of our acid soils, the other option is to switch our poorest-performing cropping paddocks into a legume-dominant pasture or sow a multi-species cover crop and run more sheep.”
More information: Craig and Fiona Marshall