THE use of nitrogen fertiliser to manipulate cereal crop structure was the topic for the latest Forward Farming demonstration, held at Andrew Manfield's Hessleskew Farm, near Market Weighton.

Mr Manfield set the scene by explaining how the naturally-occurring variability in crop density within fields, due to such influences as pests and drought, meant that different parts of the field might require varying rates of fertiliser to optimise yield. To test the theory, a winter wheat field trial had been set up on the farm using two seed rates (100 and 200 seeds per metre squared) and three rates of early nitrogen (40, 70 and 100kg/ha).

Mark Tucker, of Yara UK, presented the trial findings to date, which clearly demonstrated that early nitrogen application can be used to increase the shoot numbers in thin crops to the level required for optimum yield. The trial showed that where100kg of early nitrogen was applied on March 9, shoot numbers in thin crops had increased by a remarkable 144pc. An average of 3.6 shoots per plant had been raised to 8.6 by the time of flag leaf emergence.

Mr Tucker explained that by monitoring crop colour and crop density, the Hydro N Sensor system enabled farmers to variably apply nitrogen within the field and therefore even up the crop canopy. "Dense areas of crop receive less nitrogen, whereas thin areas are given a boost to encourage them to reach their full potential. The trial will be taken to yield to assess the true benefit to winter wheat growers," he said.

The Forward Farming arable demonstration farm project is organised by Bishop Burton College, near Beverley. Details of future events are available from Bill Meredith on (01964) 553000.

Updated: 14:52 Wednesday, June 09, 2004