A firm focus on establishing an oilseed rape crop that’s a truly sustainable part of the arable rotation has led two progressive growers down very different paths. In the first of a new series, CPM explores the key points.

What we aim for is a well branched and deeply podded hybrid canopy

By Rob Jones

There’s no right or wrong way to establish oilseed rape, and it’s frustratingly hard to know whether you’ve picked the right path to set your crop on a course that will deliver it best potential.

But of all aspects, it’s probably establishment that has the biggest impact on the overall success of the crop – it not only delivers the right yield but ensures a proper break, making it a truly sustainable part of the arable rotation. That’s why it’s the focus of this first article in a series CPM is putting together with Dekalb, that highlights the different approaches growers are taking to achieving a sustainable crop.

And no two approaches could be more different than a max-till system in Yorks and a min-disturbance focus in Lincs. Both have their distinct benefits, however.

Max-till means Richard Wainwright gets big, leafy crops going into the winter that are deeply rooted and well spread out with thick, robust stems.

Max-till way in Yorks

Despite achieving a respectable 5.05t/ha with his OSR crop of DK Extrovert last year, Richard Wainwright’s not entirely happy. “We entered the crop into the YEN (Yield Enhancement Network) Challenge and the winning crop yielded 6.2t/ha, so ours was a bit off the pace. But we got an oil content of 47.8% which is fantastic.”

It’s an improvement on his 2016 yield – 4.65t/ha, mainly from DK Extrovert again – but below the 5.46t/ha crop of DK Expower which won him Dekalb’s national lowest cost of production award in 2015.

“What we aim for is a well branched and deeply podded hybrid canopy” says Richard, based at Birch Farm, Oswaldkirk on the northern edge of the Howardian Hills in Yorks.

“Winter OSR fits our six to seven-year winter cereals-based rotation very well. We know it can deliver cracking yields from our loamy wold and heavy clay loam over gravel ground when we get enough sunlight. What’s more, it and the spring beans we also grow give us just the breaks we need to keep on top of grassweed problems, in particular.”

There’s a ‘no-compromise’ emphasis put on achieving first class establishment and plant health, he says. That means paying close attention to keeping phoma and light leaf spot out of the canopy, not to mention slugs, pigeons and cabbage stem flea beetle.

But it’s the establishment recipe that’s far from conventional. It involves early to mid-Aug sowing after winter barley, with fast-developing hybrids at very low, variable seed rates following concentrated farmyard manure incorporation in what he calls ‘Max-till’.

Working closely with ProCam agronomist, Jim Calvert, he’s perfected this approach over the years in pursuit of his primary target of crops with 30cm of tap root by the end of Nov.

Once the barley straw is baled and removed – for the 1200 beef fatteners which form an important parallel enterprise in Richard’s family partnership with his brother-in-law, Peter Armitage and his father Ian – the regime involves intensive manure incorporation into the top soil layers with a Sumo Mixidisc.

“After around three passes with the Carrier we sow the OSR across the full width of our 3m Sumo Trio, from around 12 Aug,” explains Richard. “We’ve experimented with sowing in strips behind the sub-soiler legs but find that spreading the seed after the discs and before the packer roller gives us more consistent results. We follow this up with a good Cambridge roll to ensure the best seed-to-soil contact.

“It’s gooseberry bushes we want. So we aren’t looking for more than 15 plants/m² in March and sow at an average 30 seeds/m². With all our ground conductivity scanned and mapped, though, we vary this by plus or minus 10 seeds/m², sowing as little as 20 seeds/m² in many places.

“Some people think this is far too risky,” he says. “But, by drilling reliable, fast-developing hybrids early into decent moisture and well-fissured soils with a nice manure mulch we can be sure of getting our crops away strongly enough to survive all the things that attack them.

“Max-till means we get big, leafy crops going into the winter with few, if any pigeon runways. Because the plants are deeply rooted and well spread out they produce thick, robust stems with excellent standing power.

“Reliably good establishment means we’re not tempted to add extra seed for the slugs or the pigeons. So we’re not getting in the way of our crops’ ability to produce the open, well branched canopies they need for the most efficient sunlight and nutrient capture in seasons where pest pressures are lower than normal.”

Particularly vigorous OSR establishment takes the pressure off early agronomy – rapid and robust OSR rooting means a noticeably greater tolerance to pest damage. This and varieties with high levels of phoma stem canker resistance also give welcome autumn disease control flexibility.

As a result, only a single late-autumn fungicide is employed as a rule – mainly as an insurance against light leaf spot – and Richard sometimes even questions the need for this. A further stem extension spray in March completes the foliar disease programme.

Large, well-established crops and the nutrient buffering value of good organic matter levels take the pressure off spring fertilisation too. This is helped by the routine use of both autumn and spring trace element mixes to promote plant health and nutritional efficiency. Overall nitrogen use is typically around 170-190 kg/ha, applied in three variable splits aimed at evening out canopy development for the most condensed and efficient flowering.

“Despite generally tall crops, we avoid using PGRs wherever we can,” he adds. “The thickness of their stems and the structure of their canopies means we’re seldom worried over our crops’ standing power. That’s also why we give them the trace element and pesticide inputs they need precisely when they need them.”

He’s also a firm advocate of both pod shatter resistant varieties and pod sealants applied in mid-June, up to four weeks before glyphosate desiccation. This belt and braces approach allows him to delay desiccation for as long as possible each summer to build the maximum yield and oil content.

“Too many people limit their OSR performance massively by killing their crop too early,” he insists. “Every day of seed filling lost reduces seed yield by 1-2% and has a major effect on oil content. In particular, we don’t want to waste the slightly later-maturing pods we have well down the canopy. And we can only have the confidence to wait for them if we know we’ve protected ourselves against losing the more mature seed from higher up.

“Our recipe certainly won’t suit everyone,” concludes Richard. “But we’re getting the most each season allows us to achieve from robust, modern hybrids grown in a way that exploits as much of their potential as possible.”

Blackgrass key worry in Lincs

Consistently reliable establishment is the overwhelming OSR priority for Jim Beeden and his Frontier agronomist, Jeremy Nicholson at Flagleaf Farming in North Lincs. As well as the key to the profitability of their second largest crop, it’s an essential element in sustaining the performance of the first wheat mainstay of the 2800ha arable business.

“Blackgrass control is the driver of everything we do these days,” Jim points out. “Staying on top of it is vital to the sustainability of our whole business.”

Around a third of the cropped area is now in spring crops – mainly barley but also linseed, sugar beet, maize for AD and a small amount of spring wheat. There’s a fair acreage of cover crops and they’re firmly focused on improving soil structure and drainage.

“Winter OSR is also a major weapon in our armoury. It’s really competitive and allows us to use very effective herbicides.”

But both Jim and Jeremy have no doubt that the secret of success with OSR the 500-700ha they grow annually – both in its own right and as a break crop – lies in its establishment.

“A good 80% of the challenge with winter OSR is in its first few weeks,” stresses Jeremy. “Getting the crop up and away rapidly and evenly gives us the head start we need in dealing with the many things that can set it back at its most vulnerable stage.

“It also means we have a far more blackgrass-competitive crop and altogether less worry, not to mention expense, in achieving the consistent 30 plants/m² we’re looking for at flowering.”

For vigorous establishment, their variety of choice is DK Extrovert. “This and the DK Exalte we’ve also been growing are notably rapid in their early development, making them especially well suited to the second half of our drilling window. Their strong combination of phoma and light leaf spot resistance also offers us valuable flexibility in our spraying programme.

“Alongside these, DK Exclaim has been our first choice for our earlier drilling. It’s also very vigorous and disease resistant but less rapid in its autumn growth and especially stiff-stemmed, both of which are more important for early drillers. We’ve had this alongside V316OL which we mainly grow for the HOLL premium.”

The FlagLeaf Farming team has brought the start of drilling back to early Aug to combat the threat of flea beetle, and this season have settled for DK Expansion as the principal variety for this slot. This sits alongside long-time favourite, DK Extrovert for the main and later sowings. They’ve also sown highly vigorous DK Imperial CL for the first time this autumn on land prone to cranesbill and hedge mustard problems to take advantage of the Clearfield system.

All the crops went in with an adapted 6m Väderstad Rapid drill equipped with a Rapid Lift toolbar. This has proved a real step forward in establishment over the past year, giving excellent sowing depth control together with the least possible surface disturbance.

“We’ve reduced the variation in our sowing depth with the Rapid drill,” explains Jim. “This is adapted to sow in two bands 125mm apart behind each low disturbance leg set at 500 mm centres. The sowing coulters give us some nicely localised cultivation and very even depth in the fissured ground, with the press wheels following this up to ensure good seed-to-soil contact and trap the moisture released by the subsoiling.

“Removing the coulters we don’t need means we leave the soil surface between our twin bands of seed completely undisturbed to keep the blackgrass asleep. The new set-up also means a single roll after drilling is perfectly adequate.”

Seedbed fertiliser is another area in which significant improvements are being made at Flagleaf Farming in pursuit of better OSR establishment. Sufficient nitrogen and phosphate have long been regarded as essentials in getting the crop underway, with liquids preferred to solids for their accuracy and immediate availability.

A 16.5N, 33P fertiliser mixture is now placed in bands immediately behind each leg and ahead of the double rows of seed. This concentrates the fertiliser where it’s needed with easy reach of the developing roots without exceeding NVZ limits.

“We’re really getting reliably even establishment these days,” reports Jeremy. “This is a great boon too in giving us the confidence to consider reducing sowing rates from our current 50 seeds/m². This should make it easier for us to secure the most productive canopies.”

They’re also paying particular attention to managing straw residues ahead of the OSR crop. “It needs to be well chopped and spread for the most even drilling and to avoid the sort of protective mat that’s almost impossible to get slug pellets through,” continues Jim.

“While it does have time implications, we’re baling and removing more of our spring barley straw to swap for muck these days as it’s so difficult to reliably chop.”

The OSR establishment is a work in progress – Jim and Jeremy reckon they’ve been getting the essentials right for their conditions in recent years. And they’re continually fine-tuning as many aspects of their management as they can to progressively improve their field-to-field and year-to-year consistency.

“Winter rape isn’t a cheap crop to grow,” stresses Jim. “But providing we get it established right we know we can manage it successfully through the season to make a decent contribution to our bottom line and, as importantly, to the blackgrass management crucial to the profitability of our Number One earner, first wheat.”

Sustainable OSR

Knowing that success with oilseed rape is as much about what you do as how you do it, Dekalb is working with CPM to share the experience of successful growers with a broad range of different establishment and management approaches.

This sponsored series is all part of our role in providing trusted support and partnership to OSR growers that goes well beyond the most robust and dependable varieties.

We hope you find this series of value in helping you fine-tune your own production for the most sustainable success.