UNDERSTANDING CENTRAL TO OSR IMPROVEMENT 08-Apr-2019

Better understanding the crop has enabled Richard Budd to markedly improve the reliability as well as the performance level of 100-120 ha of oilseed rape he grows as part of his 1100 ha combinable cropping business on and around the High Weald near Hawkhurst in Kent.

 

Yields have long been on the high side of 4.5t/ha from ground that has grown little, if any, OSR in the past. But he has been able to push them to an even healthier and far more consistent 5t/ha in recent years. At the same time, he has ensured they deliver first class black-grass control as a crucial break in his 6-7 year winter cereal-based rotation.
 

Serious cruciferous weed problems haven’t stood in the way of this either. Indeed, last year the 60 ha of Clearfield rape he grew delivered exactly the same 5t/ha average as his 40 ha of conventional OSR.  And at 5.7 t/ha, the 5.5 ha ADAS YEN crop of his preferred Clearfield variety, DK Imperial CL was the fifth highest yielding in the 2018 competition.


“Resistant black-grass and a particular verticillium threat makes a wide rotation essential for us,” he explains. “We keep things flexible on a field-by-field basis but we won’t grow rape  more frequently than every five years and prefer it one in seven. We sow well into September at 70 seeds/m2 – even with hybrids – and in 33 cm bands through a Sumo DTS strip-till drill.  This gives us the time to glyphosate-off a good stale seedbed flush of cereal volunteers – even if the rape follows second wheat rather than barley. It also gives the least seedbed black-grass germination and the most competitive crop.

“It has taken us time to get things right with the DTS. But we’ve sorted out the best coulter pressure and other settings for our ground to get the consistently even depth of sowing we want. Working to 6-8”, the loosening legs provide a good linkage to the drainage.  And the Dutch coulters we use sweep away then replace the chopped straw we find such a valuable surface mulch.

 

Strip till drilling for the past six years has improved the resilience of Richard’s soils no end, while always running in the same tramlines with a 30m CTF approach means he rarely has much in the way of compaction to deal with these days. He always used to sow towards the end of August, but found himself having to re-drill far too often following the deluge of cold rain that always seemed to arrive over the bank holiday and horrendous early competition from cereal volunteers.

Having tried various straw rakes over the years, Richard has found his ideal  solution in a Vaderstad Carrier with cross-cutter discs. Operating at just 10-15mm, it scuffs the entire soil surface to encourage the best volunteer growth for spraying-off the day before drilling.

Contour rolling with a slug pellet applicator  immediately after drilling completes the establishment regime.  DAP is applied at 30 kg/ha at the cotyledon stage – once Richard knows he has a crop. For the same reason pre-em herbicides are firmly off the agenda and the Clearfield system suits him well.

“We set our OSR up as well as we can at drilling and give it everything it needs to fulfil its potential,” he insists. “But we’re only prepared to spend on inputs when we have a crop that deserves them. People think we’re nuts not starting to drill until the second week of September, sowing a hybrid at 70 seeds/m2 in bands and holding-off on early inputs. However, last year’s YEN crop proved to us that we’re on the right track.  It wasn’t sown until September 22 and it still out-performed all but four of the other crops in the competition.
 

“Later sowing has also enabled us to avoid any problems with flea beetle at a time when so many growers round here have been having serious issues.  For us, it’s all about dealing with volunteers and setting-up the ground well enough beforehand, then drilling thickly when the conditions are right.  Vigorous varieties take-off like a rocket, get their feet well down and compete aggressively with both weeds and pests.

 

“Cleranda in early October does a great job in cleaning out the charlock, runch and hedge mustard that would otherwise make it impossible to grow OSR on much of our ground and limit us to winter beans as a cereal break.  Wherever we see a good flush of black-grass coming through Centurion Max in late October is very valuable in keeping on top of it until we go in with the Kerb in mid-December when it has the best residuality.”

 

With rather large, thick crops coming out of the winter, Richard Budd takes a little and often approach to fertilisation, applying two splits of Sulphur-N followed by a final application of urea at yellow bud. He routinely employs Caryx for growth regulation at early stem extension to avoid the 6-8’ tall crops that would otherwise lose yield through leaning in the summer winds, even if they didn’t lodge.

 

Trace element nutrition is an important part of his programme too, but only to meet actual need identified through regular tissue testing. Naturally acidic soils mean regular liming is essential and he is well aware of the extent to which this can cause availability issues.

 

“Continual improvement is essential for us,” insists Richard. “The YEN competition is really valuable in benchmarking what we do and highlighting areas like rooting depth, sulphur and magnesium nutrition we may be able to further fine-tune. Another thing it’s confirmed is the importance we’ve always attached to late desiccation. We didn’t go in with the glyphosate until July 5 last season by which time the top of the crops had been brown a good while and most others around us had been sprayed for at least a week. By waiting until the stems underneath are beginning to senesce we give ourselves valuable extra days of grain fill which certainly show through in the yields we achieve.”