Grass swards are at their most productive in their first year. Dry matter yield and energy content of the grass will then decline year-on-year. Good grassland management and the use of quality grass seed mixtures will promote output but, yields from a young sward will always out-perform older swards.
Limagrain’s latest grass trial results have demonstrated the yield benefits of the younger sward, and the benefit of high quality grass seed mixtures versus a control.
The trials conducted over four consecutive years, from 2017 to 2020, showed an average decrease in yield of nearly five tonnes per hectare – around 40% – from year one to year four.
While some mixtures showed greater performance than others – all had a significant decrease in yield over time. This, according to the company’s forage crop manager John Spence, is typical even in a well-managed sward.
“Some growers will see much greater yield reductions,” he says. “Management and grass seed mixture will affect forage production over time.”
These latest trial results reinforce the value, and cost-justification, of reseeding as part of good farm management.
“This loss of nearly five tonnes of dry matter yield per hectare in four years would provide the energy for £3,280 worth of milk based on a milk price of 30p per litre. “Reseeding is estimated to cost between £430 and £700 per hectare, so there’s a clear return on investment here.”
Value-added swards
Limagrain’s trial results also showed that using proven grass seed mixtures can provide added yield and feed value.
“Take one of our trial mixtures Monarch Silage & Grazing,” says Mr Spence. “This medium-term mixture yielded 8% above the control under conservation management and was 12% higher yielding under grazing management.
“The mixture also added feed value with improved digestible fibre of 2.5% under grazing management and 4% in conservation systems, compared with the control.
“If we consider that a 1% improvement in this digestible fibre – dNDF – can increase milk yields by 0.25kg per cow per day, a 4% increase is worth an extra litre of milk per cow.
Based on a milk price of 30ppl, this is an extra £300 of milk income a day for 100 cows.”
A mixture with credentials
Monarch Silage and Grazing mixture is LGAN accredited that identifies it as having a proven ability to deliver superior nutritional value, while maintaining excellent agronomic qualities and yield. Limagrain mixtures with LAGAN accreditation are all supported with independent trial data that demonstrate their added feed value.
Monarch Silage & Grazing includes medium and late tetraploid and diploid ryegrasses and white clover. All the seed is tested to ensure quality standards are met and it is treated with Headstart® Gold to ensure rapid and reliable germination.
“The latest trial data, and the return on investment of adding value through a reseed and by using high quality mixtures makes for good reading and supports the role of these practices in successful management,” adds Mr Spence
