No need to seed: restoring species‐rich grassland on former arable fields by natural regeneration

Abstract Introduction Over the last century, agricultural intensification has caused substantial losses of semi‐natural species‐rich grasslands. One means of restoring grassland habitat is to abandon farmed land, followed by mowing and/or grazing of the established vegetation to facilitate meadow diversification. Objectives This study investigated post‐abandonment vegetation change for an ex‐arable field in eastern England following cessation of crop cultivation in 2005 and commencement of an annual hay meadow mowing regime over 2011–2022. Methods Vegetation surveys were undertaken every 2–3 years following 2011, with plants recorded along permanent transects using 1 × 1 m quadrats. In parallel, all plants present in the meadow were recorded via an exhaustive walk‐over survey. Results After 3–4 years of mowing, weedy annual plants were largely replaced by perennials, with an increase in legumes and a major spread of two orchid species: Dactylorhiza fuchsii and D. praetermissa . After 11 years of mowing the field had become a species‐rich meadow supporting locally scarce species. Communities shifted from a ruderal open vegetation to one encompassing a variety of high conservation value mesotrophic and “unimproved” grassland vegetation types, with British National Vegetation Classification units MG8 ( Cynosurus cristatus–Caltha palustris grassland), MG5 ( C. cristatus–Centaurea nigra grassland) and MG4 ( Alopecurus pratensis–Sanguisorba officinalis grassland) emerging as potential restoration endpoints. Conclusions Despite its isolation in an arable agricultural landscape, a rapid decadal‐scale post‐arable diversification of the meadow's vegetation is evident. The mechanisms facilitating this remain obscure, but it is suspected that deer‐mediated seed dispersal may have been important to species arrival.