Lowland Grassland Timescales to Achieve Favourable Condition Introduction

Rehabilitation of existing priority lowland grassland Timescales to achieve favourable condition Introduction This advisory note identifies the length of time that different management practices take to achieve favourable condition on existing priority lowland grassland habitats. The timescales and interim indicators can be used to assess the trajectory of site condition and whether habitat condition is progressing in a positive or negative direction. Lowland grassland priority habitat encompasses a range of species-rich semi-natural grassland communities. They have declined over the second half of the 20th century, a variety of causes including agricultural improvement, urban development and abandonment where management cannot be continued or is no longer economically viable. Lowland grassland is still under threat and rare, covering around 3% of England’s area, with an estimated 7,282 ha of lowland meadow, 870 ha of upland hay meadow, 38,687 ha of lowland calcareous grassland and 20,142 ha of lowland dry acid grassland (Bullock et al. 2011). The priority lowland grassland habitats featured in this advisory note include: Lowland meadows – including dry and floodplain hay meadows and pastures. National Vegetation Classification (NVC) categories MG4-5 and MG8. Upland hay meadow – dry and floodplain hay meadows and pastures that usually occur at less than 300 m in upland landscapes, and are generally managed in a similar manner to lowland meadows (mostly dry grassland). NVC categories MG3 and upland forms of MG8. Lowland dry acid grassland – including species-rich bracken stands and inland dune grassland. NVC categories U2-U4, U4/20 and SD10-11. Lowland calcareous grassland - NVC categories CG1-10. Rehabilitation of existing priority lowland grassland 2 The botanical composition of floodplain meadows (MG4 and MG8), including positive and negative indicator species and the management related to rehabilitating and maintaining these grasslands, has been included in this advisory note. However, these grasslands are also a function of specific hydrological regimes, and timescales for rehabilitation relating to water management has not been included. Priority lowland grassland habitats not included in this advisory note are purple moor-grass and rush pasture (M22- 26) and calaminarian grassland (OV37). Lowland grassland management is largely a balance between under- and over-management of these mid-successional habitats, with a closed sward that may be forb-rich in calcareous and neutral grassland or grassier in acid grassland. Scrub is an integral part of some of these grasslands, providing part of the habitat mosaic. Not every management practice is suitable for every site. For example, although many neutral hay meadows are managed with a cutting and aftermath grazing regime, this type of grassland can also be legitimately managed as pasture. Calcareous grasslands are usually managed as grazing pasture but there may be situations where grazing may not be suitable or practical, such as where the infrastructure is not present, and the grassland has to be cut instead. Also, each site will have a different starting point and it is not possible to cover every situation and reaction to management. No judgement is made within this advisory note on the most appropriate management practice and no advice is provided on management prescriptions. For information on the suitability and application of management practices, seek assistance from land management advisers and specialists, and consult available literature including: The Lowland Grassland Management Handbook (Crofts and Jefferson 1999; termed ‘lowland grassland handbook’ throughout this document); The Wet Grassland Guide: managing floodplain and coastal wet grassland for wildlife (Benstead et al. 1997) A Practical Guide To The Restoration And Management Of Lowland Heathland (Symes and Day 2003; termed ‘lowland heathland management guide’ where mentioned in this document); Magnificent Meadows website – a directory of information regarding habitat management; The Floodplain Meadows Technical Handbook (Rothero, Lake and Gowing 2016); The Scrub Management Handbook (Bacon et al. 2003); Bracken Management and Control TINs 047 and 048 (Natural England 2008; 2009); The Use of Lime on Semi-Natural Grasslands TIN 045 (Natural England 2011); The Climate Change Adaptation Manual NE546 (Natural England and RSPB 2014). There is further background information on lowland grasslands and the Milestones to Recovery Project in the annex. Rehabilitation of existing priority lowland grassland 3 Lowland Grassland Condition Assessment Management of lowland grassland focuses on maintaining four attributes in favourable condition – habitat extent, forb:grass ratio, positive indicator species and negative indicator species (Robertson and Jefferson 2000). The first attribute can only be measured at a site-specific level and is therefore not covered by this advisory note. The other three attributes are measured against generic thresholds across all lowland grassland sites, although the thresholds may be adjusted on a site-by-site basis to suit the local environment. In addition, there are three proxies that can be used to determine whether the grassland is declining in condition. These include height of vegetation, litter and bare ground. Failure of these secondary attributes does not trigger the condition to be considered as unfavourable, but they can be used to initiate a management response to address the reasons why the grassland condition is declining. Formal condition monitoring may be undertaken once every five or six years, but informal monitoring (site checks) may be undertaken at more regular intervals. Figure 1: Hypothetical model linking habitat condition with management and timescales on a neutral grassland. Cutting Cutting and aftermath grazing Relaxed grazing *T -Timescale with interim indicators Unfavourable declining Favourable condition Unfavourable declining Unfavourable recovering Unfavourable condition 1 Prior to management 2 Implementation 3 Implementation of cutting 5 Relaxation of cutting and grazing of grazing Management over time Condition attributes FG - Forb:Grass ratio FG FG FG FG FG Pos - Positive indicators Pos Pos Pos Pos Pos Neg - Negative indicators Neg Neg Neg Neg Neg Rehabilitation of existing priority lowland grassland 4 The outcome of condition monitoring is used to assess the status of the site, indicating whether it is in unfavourable or favourable condition. This results in the condition assessment of unfavourable recovering defined as “all the necessary management measures are in place to address the reasons for unfavourable condition. Habitat and species features will ‘recover’ to a favourable state, but in many cases this takes time” (Natural England 2008). Grassland sites may remain in unfavourable recovering condition for a long period of time depending on the implementation and maintenance of management, reaction of the habitat and unforeseen events, such as a wet summer, which may delay or stop management. Figure 1 is a conceptual model of the relationship between grassland management and change in site condition. The condition of a site is a summary of the status of all the mandatory monitoring attributes, and each attribute needs to be achieved before the habitat is considered favourable. This is described in section 3 of figure 1, where cutting and aftermath grazing have been implemented on the neutral grassland. Different management interventions may be undertaken as time progresses, usually resulting in improved condition, such as ‘cutting’ or ‘grazing’ or ‘cutting and grazing’ as suggested in figure 1. The management depends on the type of grassland, and further information on the most appropriate management used for different types of calcareous, neutral and acid grassland are included in the annex. Improvement in condition may be slow and can fluctuate, and it can be difficult to determine progression of recovery. As a consequence, it is not possible to readily judge where within unfavourable recovering condition the site falls and how long it may take to reach favourable condition. There is also the potential to hasten recovery by undertaking different management or a combination of management. In addition, some management practices or levels of implementation may result in a decline in condition depending on the site – for example, the cessation of aftermath grazing suggested in figure 1. The length of time it takes for lowland grassland sites to reach favourable condition depends on the starting condition of the site and the management interventions employed. Each site is different and management that may result in a quick recovery to favourable condition on one grassland may take much longer or not be successful at a different site. In addition, there are cases where the initial trend following initiation of management is negative, before then having a positive effect. Thus, assessments based on early monitoring may be misleading and there is the potential that the management may be considered to be detrimental. To map the recovery of a site, timescales and interim indicators are required to understand how it is progressing. This advisory note provides generic guidance on these timescales, and this information could be used on a site-by-site basis to identify where within the broad unfavourable recovering category condition falls, and how long it may take for the site to recover depending on the management intervention undertaken. Rehabilitation

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