There is an increasing interest in ‘tall grass’ grazing and extended pasture resting periods in grazing rotations to improve soil health, build organic matter and ultimately produce more forage growth. This type of grazing involves high stocking densities, frequent moving of livestock and longer resting periods (similar to ‘mob’, ‘cell’, adaptive multi paddock’ and ‘regenerative’ grazing). It is thought the greater leaf area and thus opportunity for photosynthesis leads to increased root growth and depth, and this root mass helps feed the soil microbes (e.g. bacteria and fungi). Whilst these practices are more common in beef and sheep grazing, there is a concern amongst dairy farmers that they may not meet the higher calorific demand.
The group are looking to fill this knowledge gap by testing how longer resting periods and the length/incorporation of residuals impacts soil health and forage quality over three years, with implications on productivity milk yields.
Where participants are comfortable in achieving sufficient nutritional value to feed the milking cows, they will stock with milking herds on the trial plots. Where they are less sure, they will stock with dry cows or young stock - highlighting that you may be able to achieve the same soil health benefits of tall grass grazing on a dairy farm, even without grazing all fields with lactating dairy cows.
They are being supported by farming advisors and researchers at the Soil Association and Harper Adams University to run this field lab. The group are motivated by the need to minimise feed input costs, increase self-sufficiency in livestock feed and improve soil health (a policy priority in the SFI for 2022).