A new service to help growers lift crop yields through better targeted nitrogen dressings has been launched by Kemira GrowHow.

The Loris precision application maps use remotely sensed images to assess crop biomass, from which software generates variable rate treatment maps.

Overall yield increases of 3% have resulted from using the system, said the firm’s Robin Thompson.

“Not surprisingly we have found that fields which benefit most from variable rate nitrogen are those with the greatest inherent variability. You can choose to provide more fertiliser to the best parts of the field or to give more to the poorer parts.”

Loris is compatible with all main tractor manufacturers’ GPS systems, although for users without GPS, fields can be zoned to allow fertiliser to be applied through a conventional spreader, rates being varied manually for each zone, he added.

Loris has an initial down payment of £500 and costs £5/ha for each field treated.