Grassland farmer Willie Watson has 300 cows and 220 breeding ewes on 243 hectares at Muir Farm, in Mauchline, Ayrshire.
He advocates a grassland management system firmly focused on maintaining soil nutrient levels and the quality of grass leys, and approaches grass in the same way as growing an arable crop. “I know it is vitally important to keep soil pH in excess of 6 to give rye-grass the chance to fulfil its genetic potential. I also work hard to maintain the right nutrient levels, particularly potash and phosphate,” says Mr Watson.
“Each year we do soil analysis on sections of the farm, more recently using GPS testing and mapping on some areas, and we also analyse slurry and grass.” In 2014 Mr Watson topped the leader board in Yara’s Grass Prix – delivering the best value of grass per hectare at £2,943. That year the silage fields received 45,000 litres of slurry per hectare applied around the last week in February, followed by 314kg/ha YaraMila Sulphur Cut (22-4-14+7.5SO3) fertiliser in mid-March.
Greg Dall, Yara area manager, who advises Mr Watson, says: “Ten days after that base dressing of 22-4-14 we applied YaraBela Prilled N. Then after the first cut, as soon as the grass was off the field, 39,000 litres/ha of slurry was applied, injected to give a better uptake of nutrients, and YaraMila Sulphur Cut at 375kg/ha.”
Over the first two cuts the nutrients applied as mineral fertiliser were 194kg N, 28kg P2O5 and 97kg K2O at a cost of £247/ha. This compares to average values in Scotland of 117kg N, 32kg P2O5 and 46kg K2O at a cost of £124/ha. Looking at the value of the crop, compared to buying-in the same amount of ME as brewer’s grains, Mr Watson achieved £2,943/ha.
This gave him a margin over fertiliser of £2,695 compared to the average farm practice which achieved £1,408/ha and a margin of £1,283. A key insight was the importance of treating grass as an arable crop, not least by completing a nutrition management plan ensuring all nutrient requirements are met and balanced. Another strong learning point was the benefit of reseeding.
“We also take a rigorous approach to reseeding,” says Mr Watson. “Quality and young grasses perform better and so we keep up a good rotation, monitoring every field in terms of yield. As soon as one underperforms we ask for specialist advice on the best variety choice available.”