Welsh Soil Project Project Update July 2024

The Welsh Soil Project is in its third year by now, with an additional 15 farms soil sampled in Autumn 2023 and a further 24 farms in Spring 2024. The methodology was altered slightly for Years 2 and 3, with a total of three fields sampled on each farm, determined by their management intensity (Table 1). It was desirable that each field had a minimum of one mature hedge bordering it. Arable and herbal ley fields were excluded from the project.

Table 1. Field categories selected for soil sampling.

Field number

Field type/management

1

High intensity - intensive field with high nutrient requirements, high pasture production, high stocking rate, a minimum of 2 silage cuts taken off the field annually, low plant diversity in general (ryegrass and clover dominated). Example field = best silage field, used to finish lambs

2

Medium intensity - an intermediate field with medium nutrient requirements, moderate pasture production - predominantly grazing only fields, one silage cut taken off the field annually, intermediate plant diversity. Example field = lambing fields/ewes and lambs’ turnout

3

Low intensity - an extensive field with low nutrient requirements, pasture production is generally low, grazing only field (no silage is taken off the field), high plant diversity (e.g. timothy, cocksfoot, fescues, bentgrass). Example field = outlying land used to dry off ewes or no input field

As before, soil samples were taken from three zones within each field to account for spatial variability in soil carbon content within the field. In addition to the three zones within each field, soil samples were taken using the same method along one hedge bordering the field (within a metre distance of the hedge’s roots) to assess how soil carbon stock can differ between different areas within fields (i.e. middle of the field and beneath hedgerows).

The remainder of the methodology was consistent with that of the first year, with the addition of the soil samples taken from 0-10cm depth also analysed for pH.

Data analysis is ongoing and the results will be published in due course.