On-the-go combine protein sensors increase wheat margins

While most research trials and discussions at the pub relate to increasing crop yield, delivering the right quality grain can have a positive effect on gross margin and profit. Knowing grain protein percentage as it enters the harvester is helping Australian farmers to maximise their wheat price.

Supported by a network of bulk stores, both inland and at ports, grain has generally been transported directly from the paddock to bulk stores for export overseas. Grain growers have been price takers.

JDyer aerial

However, in the past 10 years, things have started to change. Many farmers have invested in on-farm storage. This change has been driven by several factors, including the deregulation of the grain market, privatisation of much of the central grain storage facilities and a greater diversity of crop types putting pressure on the bulk storage for specialist segregation.

Blending for profit

For several years, farmer Jonathan Dyer, in Victoria, has been using a portable grain meter to measure grain moisture and protein to try organise his harvest. “With my father and one workman I farm 2,800ha [6,930 acres] and each year 50% of this is sown to wheat – half durum and half breadmaking wheat. The remainder is conventional and round-up ready canola and legumes, including lentils and chickpeas.

“In a dry year, wheat yield may fall as low as 1t/ha [0.4t/acre], but in a good season we are producing wheat crops of 5-6t/ha [2-2.4t/acre],” says Mr Dyer. Yield variation between years and within paddocks is driven by soil-available moisture.

He also knows from his delivery notes and prices that grain protein fluctuates across the farm, but unlike his yield, he was not able to map this variation. That was until harvest 2016, when he invested in a CropScan 3000H On Combine Analyser for his John Deere harvester.

Mr Dyer’s objective was to minimise grain handling and maximise delivery price for the majority of his cereal crop. To achieve this, he blends grain as it is harvested so he knows exactly how many tonnes of each quality of grain he can then deliver.

“I have opted for a combination of on-farm and rented local storage to help me manage variation in yield and quality.” In 2016, Mr Dyer identified his high-protein grain was on heavy clay soils in the lower-lying areas prone to frost. These areas were also lower yielding, producing about 4t/ha (1.6/acre) compared with 6t/ha (2.4t/acre) in other parts. Protein ranged from 9.5% to 14%.

The protein monitor mounted on the clean grain elevator.

“Having the protein sensor on the machine has really helped, as I can quickly patch out the high-protein areas, and harvest these with the harvester fitted with the protein monitor, leaving the second harvester to deal with the low-protein areas.”

The Dyers use the chaser bin as the mechanism for blending, sending it to collect alternate loads from the high- or low-protein areas. From Mr Dyer’s perspective, successful in-field grain blending needs good information and good communication within the harvest team.

Financial benefit of protein sensor

The total yield from the 174ha (430-acre) field was 800t (4.6t/ha or 1.9t/acre) at 11.2% protein.

If it had been delivered load by load, 350t would have been sold at $141/t as Australian Standard White, 200t at $165/t as Australian Premium Wheat, 200t would have been sold at $180/t as H2 and 50t of H1 at $188/t for wheat with more than 12.5% protein. This gives a total field return of $127,750.

However, Table 1 illustrates how with blending, Mr Dyer was actually able to deliver 600t/ha as H2, 50t as APW and only 150t of ASW. This increased the return from the field by $9,650 to a total of $137,400, a 7% increase in income at negligible extra variable cost.

Table 1: Financial return from blending grain

ASW = Australian Standard White (no protein parameter); APW = Australian Premium Wheat (10.5-11.4% protein); H1 = Australia Hard 1 (11.5-12.5% protein) and H2 (over 12.5% protein).

“That is about 40% of our investment returned just from one paddock and we repeated these price improvements across our wheat crops.” Mr Dyer appreciates that not every paddock will be this dramatic and that it will depend on the price spread in the market. However, from his experience, he feels whether using on- or off-farm storage, the potential of quality blending holds significant value.

Nitrogen removal

Farming his property Tingara, on Yorke Peninsula, South Australia, Ashley Wakefield has good access to bulk storage, but is also gaining value from blending in a system he calls “active paddock management”.

South Australian grain grower Ashley Wakefield has produced meaningful grain protein maps that have supported in-paddock blending for the past five harvests.

“We use a two-field bin system with the aim of creating low- and high-protein silos, which are blended as we load the truck and deliver to the bulk storage,” says Mr Wakefield.

His long-standing interest in protein mapping started when developing rations of home-grown barley for his piggery. Moving to continuous cropping in 2003, his interest remained, but the objective became focused on the consistent delivery of grain that met higher-value protein specifications.

• Farm size; 1,200ha (2,970 acres)
• Annual rainfall; 400mm
• Soil type: grey loam
• Average dryland wheat yield: 3.7t/ha (1.5/acre)

Mr Wakefield grows wheat, barley, canola and legumes, including lentils and fava beans, on his property that has soils ranging in texture and pH, which introduce crop variation. Over the years, he has worked closely with Next Instruments, the Australian company that has developed and now markets the CropScan 3000H.

His commitment and patience have paid off. For the past five harvests, he has produced meaningful grain protein maps that have supported in-paddock blending. He is also using the protein data to help plan crop nitrogen management, but this is proving more challenging.

Fertiliser trials

In trials in 2016, a very wet spring, he ran a production-scale strip trial across a paddock of wheat. Historic yield and soil data were used to create high-, medium- and low-yield zones.

The seeding nitrogen by yield zone was high 80kg/ha (71lb/acre) of urea, medium 60kg/ha (53lb/acre) and low 40kg/ha (36lb/acre). Across each zone three treatment strips of urea were applied in-crop at 0kg/ha, 60kg/ha and 120kg (0lb/acre, 53lb/acre and 107lb/acre).

While the maximum fertiliser rate on the high-yielding zone was 200kg/ha of urea and on the low-yield zone it was 160kg/ha; neither the yield nor protein followed. Indeed, in this year the highest yield (3.10t/ha or 1.3t/acre) and highest protein (11.1%) were both reaped from the “low-yielding zone”.

Protein map

“The highest yield and protein came from the low-yielding zone where it received the additional 120kg [265lb] of in-crop nitrogen. In this wet year it suggests the crop in the low-yielding area was able to mine nutrients left in the [soil] profile from crops grown before the adoption of variable-rate inputs.

Collect reliable data

“It is still early days for us to understand the relationship between soil and protein, but at least we are now able to collect reliable data.”

When Mr Wakefield is able to crack the relationship between nitrogen removal and required replacement, he anticipates substantial savings in urea. In the meantime he is enjoying delivering high volumes of wheat and barley to target protein specifications and the financial rewards that brings.