Spring oat opportunities

With the right modern agronomy, oats offer one of the most attractive spring cropping options for difficult black-grass ground, in particular, believes Agrii northern R&D manager, Jim Carswell. Not least with the increasing demand for gluten-free and other ‘healthy’ foods.

As well as a true cereal break, Stow Longa work shows oats are more competitive with grassweeds than other spring cereals. Agrii costings reveal them to be one of the highest margin potential spring crops for 2018.

At the same time, they have much greater sowing date flexibility and are noticeably more tolerant of low pH and wet soils than either spring wheat or barley, They also leave a much better soil structure for the following crop courtesy of their highly-fibrous rooting.

Jim Carswell.

“Spring oats today are perfectly capable of delivering a good 7-8 t/ha commercially,” Jim Carswell pointed out. “Indeed, we have seen 2017 yields comfortably over 9 t/ha in our national variety trials. Yet even the latest RB209 revision assumes spring oat nutrient offtakes based on just 6t/ha.

“If growers are to capitalise on the valuable opportunity spring oats offer they need to base their management on altogether more realistic performance assumptions, together with the most appropriate modern agronomy. The integrated spring oat research programme we have expanded in recent years to provide the best guidance is already paying dividends here.”

As well as identifying higher performance varieties with the characteristics the market requires, Agrii work across the country is providing the most up-to-date advice on their sowing rates, seed treatment, macro and micro-nutrition, fungicide treatment and plant growth regulation for the most consistent results.

In doing so it is underlining the particular value of spring oats as cereal break and the importance of managing them in the right way to avoid a number of key issues.

“Oats are more tolerant than other spring cereals both of sowing well into April and of more difficult soil conditions,” Jim Carswell stressed. “The later you sow it, though, the later it comes to harvest. This is a clear watch-out for northern growers.

“The in-crop weed control armoury is also very limited and the crop is more sensitive than most to herbicides in tank mixes. This and the fact that oats don’t grow away rapidly until GS31 makes effective glyphosate treatment ahead of sowing crucial.

“Because they take off so rapidly from the start of stem elongation, plant growth regulation is likely to be required in most cases. Again, however, care needs to be taken to avoid scorching damage and some contracts do not permit the use of chlormequat.

“While oats have a better natural disease resistance than other cereals, powdery mildew and crown rust can be damaging if not adequately controlled,” added Jim Carswell. “Equally, the risk from soil-borne viruses and stem eelworm means one in every four years is about the closest rotation that should be considered.”

With the possible exception of specialist naked oat varieties, Agrii trials show little value in increasing sowing rates beyond 275-300 seeds/m² in most cases.

In addition to prothioconazole treatment to protect against fusarium seedling blight, positive yield responses – together with margins over input costs of up to £45/ha – have been recorded from specialist copper, manganese and zinc as well as Take-off seed dressings.

“This is not surprising with the crop’s relatively slow start and its particular susceptibility to manganese and copper deficiency,” noted Jim Carswell. “We invariably see good yield responses to foliar applications of these trace elements as well as zinc where broad spectrum soil analyses show levels to be inadequate. And we’ve also found late applications of magnesium very beneficial.

“Instead of the traditional 100 kg/ha of nitrogen in a single dose, we recommend up to 150 kg N/ha in two splits – 50% at GS 30/31 to avoid over-tillering and the rest during May to maximise kernel fill and TGW. In later drilled situations the first application should probably be in the seedbed.

“We also recommend around 30-50kg/ha of SO₃ as standard and, like many spring crops, find fresh phosphate in the seedbed can be useful with later drillings.”

To protect against leaf loss from early mildew infections and crown rust, which is more common further south and tends to occur later in the season, Jim Carswell advises a two spray programme at around GS31/32 and GS 55. Good combinations of actives have typically given yield responses of 0.5-1.0 t/ha in his trials.

As far as plant growth regulation is concerned, he suggests a planned sequence rather than waiting for the crop to explode into growth from GS31 to avoid ‘shocking’ the crop. Where contracts allow its use, Agrii trials have shown Adjust at GS29 and GS32 to be very robust and safe. Alternatively, mepiquat chloride + prohexadione-calcium at GS 30 and then from GS32 up to flag leaf gives the greatest flexibility to deal with crops that become too lush.

“Although they typically yield 20% less than husked varieties, naked oats are a useful option too,” explained Jim Carswell. “They are as weed competitive and flexible and economic to grow as conventional husked types.

“What’s more, their yield penalty is compensated by good premiums on specific variety buy-back contracts for a variety of human as well as horse, poultry pet and wild bird food production where their higher protein and oil content and husk-free nature makes them especially attractive. They do, however, need to be handled, cooled and stored carefully to ensure stability. So they certainly aren’t for everyone.”