Lincolnshire farmer James Sardeson is just one of 50 progressive oilseed rape growers from all over the country looking to improve yields with YEN.

At 4.6t/ha, the average yield from 30ha of oilseed rape harvested last year on C. H. Sardeson’s Park Farm, Ewerby as part of the ADAS OSR Yield Enhancement Network (YEN) project was much higher than the UK average. Nevertheless, James Sardeson has set his sights on further improvement this season and hopes that ongoing participation in the project will help to achieve that objective. Having started with 66ha at Park Farm, Ewerby in 1964, C. H. Sardeson now farm 340ha of mostly medium to heavy land, the main arable crops being 100ha of winter wheat, 100ha of spring barley, 60ha of oilseed rape and 30ha each of combinable peas and sugar beet. “I decided to get involved in the OSR YEN project from the outset because of the peer review element, to meet other growers and be able to exchange information with them,” explains James.

James Sardeson, Lincolshire Farmer

James Sardeson

The Yield Enhancement Network aims to help members close the gap between their crop’s current yield and its potential productivity. The concept is that to understand yields, crops should be regarded as converters of solar energy into edible energy and their performance analysed accordingly to help growers know their yield potential and identify what factors are limiting. 

The YEN approach considers the yield potential of the crop in any season and compares it to the actual figure which is achieved by looking at its development, the basic resources available to it in terms of light energy and water, then assess its success in capturing those inputs and using them to form seed. “What I found interesting is that the organisers estimated our theoretical potential oilseed rape yield at between 12t/ha and 13t/ha, based on a variety which has yet to be developed,” James explains. “That means that with the genetic material which is currently available we are running at about 35% of the crop’s potential maximum yield.”

Last year he grew 30.75ha of the restored hybrid oilseed rape variety V316, a high oleic, low linolenic (HOLL) type with medium-to-early maturity, high lodging resistance and high stem stiffness. After straw from the previous crop of milling wheat had been baled 165 kg/ha of diammonium phosphate (DAP) was applied and the seed broadcast behind a Simba DTX one-pass cultivator, then rolled in. In January, fertiliser specialist Arthur Baldwin from his fertiliser supplier ACT Ltd took several soil samples from the field using the CF Fertilisers’ N-Min system, which enabled him to provide recommendations as to the optimum rate of nutrients.

Arthur Baldwin, ACT

N-Min sampling revealed that the heavy loam soil at Park Farm contained 26kg N/ha of Nitrogen in Nitrate form, together with 1kg N/ha as Ammonium, giving a total SMN of 27kg N/ha, which when added to the 35kg N/ha of AAN gave a total Soil Nitrogen Reserve of 63kg N/ha. The GAI amounted to 0.75, equivalent to 37.5kgN/ha, giving a total SNS of 100.5 kgN/ha.

Based on an estimated oilseed rape yield of 5t/ha, the CF Fertilisers’ N-Calc system recommended a total of 238 kg N/ha be applied, 74 kg N/ha at stem extension in the form of 274kg/ha of DoubleTop (27N + 30SO3), a high-quality granulated product combining Ammonium Sulphate and Ammonium Nitrate for crops that have a high Sulphur demand. It also recommended the application of 74kg N/ha in the form of 214kg/ha Nitram 34.5%N at the green bud stage, followed by 90kg N/ha from an additional 261kg/ha Nitram at yellow bud.

James applied 285kg/ha of DoubleTop on 2 March using a GPS-controlled 24m Kverneland Exacta Geospread, followed by 270 kg/ha of Nitram 34.5%N on 22 March, both products having been used at Park Farm for many years because of their consistent quality and how well they handle and spread. The OSR YEN crop was left to ripen naturally and was the last field of oilseed rape to be harvested, the combine rolling until two in the morning at the end of July to gather the crop safely in before two weeks of rain set in.

To average 4.6t/ha across 30.75ha was an excellent performance, but this year James will increase the amount of Nitrogen to 250kg/ha and take the average yield from the best 5ha rather than submitting the average for the entire field, which should be beneficial. “During the first year it was more a question of us getting to know the organisers and them getting to know us,” he points out. “But I did learn that despite there not being massive differences in the way that most of the participating growers do things, there were sufficient nuances for the data to come out of the project over time to prove interesting and beneficial.”