Multi-species leys have a valuable part to play in helping dairy farmers build resilience into their businesses but should ideally be based on only three main plant types and, to be effective, include varieties that are proven to perform in the UK.
This is the message from forage experts Germinal, who will launch their Aber HSG Multi-Species herbage mixtures at Dairy-Tech 2019.
With versions available for grazing or cutting, the new mixtures contain at least 50% high ranking Aber High Sugar Grass perennial ryegrasses alongside timothy, white and red clover (legumes), and perennial chicory and plantain (deep-rooted herbs).
“An effective multi-species sward should contain a good proportion of quality grass, compatible legumes to fix nitrogen, and deep-rooting herbs that add diversity, tolerance and additional nutritional value,” says Helen Mathieu of Germinal GB.
“This balanced combination creates a sward that will be more resilient to extremes in the weather and still deliver high dry matter yields of quality forage. Multi-species leys of this kind have an important role in progressive forage-based dairy businesses, either as part of a rotational grazing platform or as silage leys.”
The concept of combining plants in a sward with complementary characteristics has increasing independent evidence to support it, but the mixtures that have been tested adhere to the simple rule of three main plant types. They are also comprised of highly ranked varieties that are known to perform in UK conditions.
“Trials show that plants with different – but complementary – root structures can lead to more effective use of soil nutrients, giving an overall advantage compared to monoculture swards,” adds Helen Mathieu. “This is particularly so with the combination of nitrogen-lifting and nitrogen-fixing species.
“Using deep rooting species, such as perennial chicory or plantain for example, means nutrients are being taken up from a different part of the soil profile than is the case with shallower rooting ryegrasses. Having a range of different species will also mean multiple sources of protein, energy and minerals, presenting a more complete nutritional profile.”
Ms. Mathieu urges dairy farmers to apply the same rationale when selecting a multi-species ley as should be applied to any grass mixture or arable crop selection.
“We always stress the importance of growing and managing grass as a crop and that starts with the attention given seed selection,” she says. “Ensure you have varieties that are highly ranked on the independently compiled recommended list or descriptive list or insist on knowing what varieties are included. This is particularly important with species such as perennial chicory and plantain, as there is massive variation between the top varieties bred for purpose and other material.
“In addition to bringing to market the high-ranking grass and clover varieties from IBERS Aberystwyth University, our mission at Germinal is source the best varieties from around the world. Having sourced the best material, we then test it in the UK – including at our own research station – to ensure the best possible performance in the field.”