Grassland offers many benefits, particularly with multi-species leys - central to this is the root system. We often hear about deep tap roots; these are great for soil structures and lifting nutrients from deeper in the profile but a varied root system of wide, branched, fibrous and deep roots brings the most benefit. It is important to remember that root mass is just as important as root depth.
Extensive root systems help soil stability, drought tolerance and water infiltration, improving the soil structure and allowing more space for air, water and nutrient cycling. Roots exude unique chemicals which help to feed a diverse population of soil microbes which, in turn, further improves nutrient cycling to the plants. Soil stability and soil cover are really important to prevent both erosion and run off. Healthier soils = healthier plants = healthier livestock and a healthier whole farm ecosystem
The inclusion of legumes such as red clover or lucerne are really good for soil structure, with their tap roots, but they also fix atmospheric nitrogen. This reduces the need for artificial application to grassland – really important, given the rising price of nitrogen fertiliser and its significant contributions to farming’s greenhouse gas emissions. More so, it can leave residual nitrogen for subsequent crops in the rotation – some farmers are finding that they can reduce nitrogen inputs by as much as a quarter in a first wheat following grass, while boosting yield by 5 per cent or more. Legume mixes can also reduce the farm’s bought in protein requirement for livestock.
Where there is grass and forage, generally there is livestock and the livestock itself contributes by recycling nutrients back via dung and urine, while any trampled forage breaks down into the soil.
Carbon is one of the key drivers of course and there is a vast amount of research to show that the longer a grass sward is retained the higher the levels of carbon compared to when it was in arable use. Work published by ADAS in 2011 showed a 24% increase in soil organic carbon after 6 years reversion from arable.
Top tips on introducing livestock into an arable farming system and what other forage crops to utilise to help the arable rotation
Firstly, decided on the sward, there are a broad range of species, and it depends on the exact situation, be it beef sheep dairy, silage, grazing etc. White clover is an obvious choice but red clover is an increasingly popular option, as is lucerne. A number of other legumes species are becoming more widely used such as annual clovers like crimson or Persian, Birdsfoot trefoil, sainfoin. Forage herbs are also gaining momentum, with chicory and plantain the most common but there are others such as caraway, yarrow and salad burnett.
Brassicas are another option. This short term catch crop includes stubble turnips or forage rape. These can be established earlier for summer feed, or later for autumn or winter feed and the more maincrop forages kale. Fodder beet is also seeing increased interest.
If you are renting livestock the best advice is to work with the livestock farmer whose cattle or sheep you are introducing – they will have their preferences and own requirements. You will need to find a solution which fits with your own enterprise while solving the challenge.
Targeted at managers of arable-based systems who are thinking about livestock opportunities for the first time, this AHDB guide includes sections on leys, cover crops, forage crops, maize, outdoor pig production and manures.