In 3,291 soil tests carried out on beef and sheep pasture by EBLEX, with the Environment Agency (EA) and the Farming Wildlife Advisory Group (FWAG), only a shocking 2% of fields had the perfect nutrient levels to support good grass growth.
43% had a pH level below the ideal 6, which means grass yield will be reduced. A low pH also affects the availability of other nutrients, like nitrogen (N), phosphate (P) and potash (K).
In 28% of the fields sampled, the P level was over the target index 2. Fields above this must be carefully managed as there is a huge risk to the environment from leaching, and it also wastes money if more phosphate is applied in ignorance.
Where P is below target, which was the case for 46% of fields, root development may be affected, meaning the grass is less efficient at taking up nutrients and at more risk from water stress.
Almost half the fields sampled were also below target index for K (2-), affecting nutrient uptake and utilisation. This is particularly crucial for silage fields.
27% of the fields had a K level of over 2 and present a significant risk of grass staggers among livestock and luxury uptake in silage crops, which leads to lodging.
66% of fields sampled had a high Mg level over 2, which reduces N and K efficiency. High Mg soils are also difficult to cultivate as they form big blocks that are hard to break down.
This is definitely a case of if you don’t know what your soil indices are, how on earth do you know what fertiliser to put on and how much?
Dr Liz Genever, EBLEX sheep and beef scientist recommends sampling fields every five years, in the same season and at least two months after the last application of manure, fertiliser or lime.
More details in the excellent EBLEX manual ‘Improving Soils for Better Returns’ – email firstname.lastname@example.org or follow this link to the EBLEX website: