“There’s a lot to be gained from giving sheep a good bite from a quality grass sward,” says Limagrain UK’s Forage Crops Product Manager, John Spence.
“Both ewe and lamb performance will improve if there’s good grass of high feed value on offer through the season.”
It’s well known that grass yield and feed value falls away after a peak in year one. Whilst good grassland management will help to protect yield and feed value, it won’t alter the trend.
Recent results from a Limagrain four-year trial on grass plots using more than 30 mixtures, found that yields fell by an average of 40% from year one to year four. Grass and feed quality was measured through the season – not just in spring – under both grazing and conservation management.
“Spring is a good time to access the quality of the sward,” adds Mr Spence, “and to decide which swards would benefit from a reseed. Reseeding is estimated to cost between £430 and £700 per hectare, depending on cultivations needed, but this is easily justified in additional yield and feed value, compared to older swards or those in poor condition.”
Upgrade the mixture
Farmers can add more value to their reseed by choosing their mixture carefully. “Grass-seed mixtures will have a number of grass varieties included and these will each play a part in the yield, feed value, disease tolerance and growing pattern through the season,” says Mr Spence.
It makes sense to choose a mixture that has demonstrated its performance in mixture trials, as well as having a proven track record on-farm. It costs the same to grow ‘good’ grass as ‘bad’ grass.
“Our trials showed an increase of up to 8% in dry matter yields between the best mixtures and the control, and up to 2.5% difference in digestible fibre content of the grazing mixtures.”
A good sheep mix
A mixture with reliable performance in a range of conditions best suits sheep producers. “Select a mixture with mid – or intermediate – and late perennial ryegrasses,” says Mr Spence.
“Ryegrasses are the cornerstone of UK grass seed mixtures, due to their persistency and high yield characteristics, and one with mid-and late-season varieties will add extra ground cover and persistency throughout the grazing season.
“Including Timothy is ideal as it grows in early spring, before the ryegrasses, and then has another growth surge in mid-summer, when might ryegrasses slow down.”
He also encourages farmers to use a mixture with white-clover blends that, as a legume, has nitrogen-fixing abilities. White clover also has a high feed value and contributes significantly to liveweight gain. “Clovers are the single most important component of a mixture when it comes to liveweight gain in lambs,” he adds.
Castlehill in the limelight
Mr Spence highlights Sinclair McGill’s long-term mixture Castlehill as an ideal choice for sheep farmers. “It’s highly reliable and consistent for most soil types and climate,” he adds.
It is the mix of grass varieties that gives Castlehill the edge with a combination of specialized mid- and late-perennial ryegrasses and a good proportion of Timothy, plus some white clover.
“These are the core components. We have a variation of Castlehill, particularly suited for Scotland and Northern Ireland, which includes some Meadow Fescue. This variety is nutritious and leafy and will out yield the perennial ryegrass under low fertility conditions.”
The relatively new, high-performance intermediate tetraploid perennial ryegrasses Pensel and Timing are included in Castlehill.
Pensel brings high sugar content and high digestibility, and it stays leafy for longer than many other intermediate perennial ryegrasses. It also adds disease-resistance benefits to the mixture, particularly against Crown Rust, Drechslera and mildew.
Timing adds a dense ground cover and a good seasonal distribution of grass, which are both merits in a sheep grazing sward.
“Timothy is also particularly valuable in sheep grazing mixtures,” adds Mr Spence. “It copes well with wetter, colder conditions, starting to grow at lower temperatures than ryegrasses. And it is very winter hardy and will grow in poor soils. It will also continue growth and maintain palatability through summer.”
While some farmers may balk at the cost of reseeding, a regular programme is good practice. “Not only does it promote yield and feed output, but it also gives farmers the opportunity to introduce improved seed mixtures,” he says.