Multi-species reseeding – the pros and cons
APEMBROKESHIRE dairy farmer is growing multi species leys to boost soil health and protect feed supply from dry conditions during the growing season.
Andrew Rees, a Farming Connect demonstration farmer, reseeded 5.7 hectares (ha) in the spring with a diverse seed mix including chicory, red clover and plantain.
Part of his programme was to improve land he had bought and to rejuvenate an older ley where soil health was poor.
Project work with Farming Connect involved comparing the performance of a multispecies seed mix to a ryegrass ley, grown alongside each other in two halves of one field.
“We sowed the seed in April and the multi-species ley has been competing well against the ryegrass,’’ observed Mr Rees, who grazes his spring-calving dairy herd at Moor Farm from midFebruary to mid-November.
“It has had a flatter growth curve through the season but in dry periods like we experienced last summer I would expect it to keep growing for longer than the ryegrass because the plants are deeprooting.’’
Multi-species leys provide livestock with nutritional benefits not available in grass and they boost soil health – but selecting a mix that matches the livestock system is important.
During an open day at
Moor Farm, independent grassland and soil specialist Chris Duller said there is no standard mix and he advises scrutinising mixes to ensure they fit the system.
While diverse species can provide high levels of energy, protein and mineral status, he pointed out that dry matter (DM) can be low.
“Cows can do well on alternative species on a dry day but in wetter conditions you might find that they can’t physically eat enough to provide the protein and energy they need to perform,’’ he said.
They can also make measuring field covers challenging.
“Red clover, plantain and chicory all grow at different heights so measuring covers to calculate growth rates can be problematic,’’ said Mr Duller.
He advised farmers not to overgraze these leys, especially in the autumn.
“With a conventional grass ley, farmers will know to graze fields to 1500kgDM/ha, but chicory, plantain and clover have crowns that can be damaged by overgrazing,’’ he said.
Attention to detail at the reseeding stage will result in better-performing leys and good return on investment, he advised.
“Reseeding isn’t cheap, but if done well all your reseeding costs can be recovered in the first year of a new ley.’’
Crucially, the seedbed conditions must be at an optimum – test the nutrient status of soils and ensure they are free of weeds and pests.
Brassicas have been used at Moor Farm as a pioneer break crop to help deliver these priorities.
The timing of reseeding is crucial – later in the season there are fewer options for dealing with poor performance.
Weed-control through grazing, cutting or topping becomes trickier in the autumn, and sprays can be less effective as temperatures drop and days shorten.
“Yes, there can be more weeds if you reseed early on in the year, but countering them is much easier,’’ said Mr Duller.
It is important to choose the right seed mix for its intended use. Mr Duller said 75% of grass seed sown in the UK is a “cut and graze mix, considered by many farmers as a safe option.
But he pointed out: “It can’t be brilliant at both, so you get a mediocre result overall. Invest some time in studying the Recommended Grass and Clover List and pick the right balance of species and varieties to suit your conditions.’’
Abigail James, Farming Connect’s south-west Wales dairy technical officer, said with reseeding costing around £200 per acre, getting it right is important.
“To get the best return on investment it is important that factors such as soil fertility are sorted out in advance,’’ she said.