Strategic re-seeding and regular soil testing can maximise grass performance. Aly Balsom reports from Grassland UK
To maximise grassland efficiency, assess individual field performance and consider strategic reseeding, said Kingshay Technical Specialist, Cath Woods.
“Perenial Ryegrass forms the basis of most long-term leys and are highly productive, giving the most response to nitrogen application.
“Throwing fertiliser at swards rich in meadowgrass, on the other hand, does not give the yield returns – a costly business when considering the price of fertiliser. Consider renovation by oversowing or, where the amount of perennial ryegrass falls below 25%, a complete reseed,” said Miss Woods.
“With overseeding costing about £80/acre, it is much cheaper option than a complete reseed at about £140/acre.”
But over-sowing could fail when done poorly. “Timing is crucial to ensure grass already present is not too competitive. Good seed-to-soil contact is also essential, so use a tine harrow to open up the sward and roll in or use stock to tread in seed.”
Over sowing could increase grass yields by 15%, said Helen Mathieu, area sales manager for British Seed Houses.
“Renovation of grass swards by over-sowing can be a good option for farmers on shallow soils, unable to plough.
“After the beginning of June, when grass growth is down, slow growth further with a low dose of glyphospate to suppress competition from the existing swards and overseed with a full seed rate.”
But when glyphospate was being used, ensure a time gap before drilling, said Robert Baker of Pearce Seeds. “Allow three weeks or a period of heavy rain to wash the chemical off the leaves.”
Spraying a grass crop with gyphosphate before silage cutting to control weeds was also an option. “You can silage four to five days after spraying. After this stage, the weeds will begin to desiccate, becoming dryer and sweeter. This will help improve their feed value in silage,” said Mr Baker.