Evaluating the success of upland hay meadow restoration in the North Pennines, United Kingdom, using green hay transfer

Abstract

Traditionally managed mesotrophic species-rich upland hay meadows conforming to the National Vegetation Classification (NVC) MG3b are one of the rarest grassland types in the United Kingdom, with substantial declines in botanical diversity over the last 50 years. Intensive spring grazing, earlier cut dates and increases in soil fertility cause a decline in characteristic positive indicator species in MG3b meadows, shifting communities from species-rich MG3b, to NVC MG6 meadows, and finally to species-poor NVC MG7 meadows. The North Pennines Area of Outstanding Natural Beauty (AONB) Partnership's Hay Time project aimed to improve the knowledge of upland hay meadows, and to investigate the success of seed addition of key positive indicator species. A landscape-scale restoration programme was undertaken between 2006 and 2012, harvesting seed from 82 species-rich donor meadows and spreading seed onto 89 receptor meadows (222.82 ha). Seed was harvested as green hay, using two types of donors: MG6 (classed as restoration, with species such as Rhinanthus minor) and MG3b (classed as enhancement, with species such as Geranium sylvaticum). All 89 meadows were monitored, with a baseline botanical survey and a repeat survey 3–5 years after seed addition. In addition, 41 meadows that did not have seed addition were monitored (controls). Species richness, diversity and floristic composition improved in 77 meadows 3–5 years after seed addition. Eighteen plant species had an increase in frequency in the receptor meadows but did not increase in frequency in the control meadows. The most successful were eight positive indicators which were annuals or fast-growing perennial plants (Anthoxanthum odoratum, Euphrasia spp., Myosotis discolor, Plantago lanceolata, Ranunculus acris, R minor, Trifolium dubium and Trifolium pratense). However, rarer characteristic MG3b plants such as Alchemilla spp., G. sylvaticum and Cirsium heterophyllum showed little signs of establishing. Botanical evidence is demonstrating that seed addition using green hay is a successful way of restoring meadows to an MG6 community. What is now needed is an effective method to establish characteristic MG3b plants. Hand-collecting seeds and establishing plug plants, alongside seed addition and maintaining traditional management practises, is one possible way forward.