High sugar grasses not only offer higher yields and herbage quality, but also cut pollution.

Speaking at the launch of AberMagic, produced by IGER and available from British Seed Houses, IGER's Richard Hayes said rumen microbes made better use of herbage nitrogen when stock ate high sugar grasses.

"We have deliberately lowered excess protein in the Aber high sugar range, as the bulk of it passes straight out of the animal. Instead, a lot more protein is digested in the rumen which reduces methane and nitrous oxide production. Cows deposit just 39% of nitrogen back in their dung compared with 42% for other grasses, and 26% of nitrogen in urine, compared with 35%."

AberMagic can also be used for ethanol production. Just 6ha of processed grass will produce enough fuel to power a bus for 100,000km.