Oilseed rape has had a good year, even in the wetter west, with above-average yields and gross output, although there have been considerable crop failures as well.

According to a report by Rural Business Research, farmers in England planted 8% less oilseed rape in 2014 at 577,000ha.

An estimated 17% of growers suffered crop losses because of cabbage stem flea beetle, with 16,000ha of the crop lost, it says.

“Of this area, an estimated 9,200ha were replanted and 6,600ha written off,” says the report.

Of course, there were also farmers who did not suffer total losses, instead harvesting some thin and patchy crops, often with high weed burdens and resulting admixture.

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According to the Adas harvest report, yields ranged from 2.25t/ha in crops with pest and drought damage to 6.2t/ha on heavier ground, resulting in a UK average of 3.6-3.8t/ha – well above the 10-year average of 3.4t/ha.

Red seeds

Oil contents ranged from 42% to 48%, and quality was generally good, says the report. “However, high numbers of red seeds have been reported in some regions where crops were harvested before they were quite ripe.”

Richard Elsdon, technical manager at United Oilseeds, says many samples had tested at 45-46% oil, but there had also been a number at 42-43%.

“I wonder if some people desiccated a bit too early – it is easy to do when you have a large area to combine,” he says.

However, almost every farmer had enjoyed larger yields than expected.

“People with really large rapeseed areas have averaged more than 4.9t/ha.

“It has been a uniformly good harvest and the western side of the country has yielded at least as well as the East, which is unusual.”

Mr Elsdon attributed the good yields to settled weather and plenty of insect activity during flowering.

“It was a dry spring, so nitrogen was released slowly, and the leaves were around for markedly longer after flowering which increased photosynthesis,” he says.

“It was also calm and sunny for the first half of the summer, so there was an extended ripening period, which maintained the seeds that had set.

“The seed grows very rapidly at the end of the season, and most glyphosate applications were seven to 10 days later than normal.”

Provisional AHDB Recommended List trial results put average yields in the east and west region at 5.89t/ha – 10% above the four-year rolling average of 5.35t/ha.

“It didn’t seem that we had a particularly good growing season – dry and cold conditions didn’t favour the crop getting away in the autumn,” says Simon Kightley, oilseeds variety specialist at Niab.

“However, the weather was pretty good in April and May. With oilseed rape, a lot of its success is down to dry conditions for pollination at flowering time.”

Candidates

Mr Kightley said he was encouraged to see so many candidate varieties – both hybrid and conventional – at the top of the provisional table.

New conventional candidate Elgar was top of the list, with gross output at 110% of the control varieties in 2015.

The three-year average results put Elgar, Windozz and Wembley all on 109% of controls, with Alizze, Nikita and the best of the current RL varieties, high-oleic, low-linolenic (Holl) variety V316OL, just one point behind on 108%.

“It is really quite exciting to see a whole set of candidates coming through with excellent yield potential,” Mr Kightley adds.

“I think Elgar is probably the most balanced variety, with good light leaf spot and phoma stem canker resistance. It is also good to see the best of the conventional varieties up there with the best hybrids.

“Producers who are worried about flea beetle and want to raise the seed rates will be able to use a conventional variety and not worry about the cost of hybrid seed.”

Among the varieties already on the list, Incentive pulled ahead of Harnas, with three-year average outputs of 107% and 105%, respectively.

“Charger is a point down at 106%, but it is still an excellent variety with short straw and good lodging resistance.”

In northern trials, provisional results put the average gross output at 5.99t/ha, 0.84t/ha above the four-year average.

“Campus (108%), the quality oil variety V316OL (107%) and Anastasia (107%) have achieved good yields in 2015,” says Mr Kightley.

Based on four-year average values, Alizze was coming in top at 112%, with Harnas and Nikita at 111% and Anastasia, Barbados, V324OL, Campus and V316OL all on 110%.

“There are very few clubroot-resistant varieties available and the good showing here of Mentor (103%), with clear daylight between it and Cracker (93%), is very reassuring.”

Amalie, the turnip yellows virus-resistant variety, scored 97%.