This blog post was inspired by two things – a series of You Tube videos from wild plant charity Plantlife and an enquiry via Facebook on the Borough Council’s practices around road verge management (which was itself prompted by a national press article on excessive cutting of road verges).
The Plantlife campaign #EveryFlowerCounts, focusing on garden lawns as resources for pollinating insects has been promoted on social media this month, but only came to my notice this week. (We are just in time to participate in a citizen science survey by counting the flowers growing in our garden lawns. Follow the link here.) It links to a previous campaign, #NoMowMay, also started by Plantlife, which has been widely adopted by nature conservation commentators on social media. This encourages gardeners to leave the mower in the shed throughout the month of May and let the first flush of lawn flowers bloom for the benefit of bees and so on.
These circumstances have been a useful prompt for a timely biodiversity blog on Connecting for Nature. I entitled it ‘On the complexities of Local Authority grassland management’ which sounds rather grand. The post actually started life as a reply to a customer enquiry. I mention this to explain why the tone may come across as rather defensive. It represents a degree of recognition that Local Authorities could always do more to promote biodiversity on their roadsides and grassland, but it is not always as simple as mowing less often. Read on- it will become clear.
The Parks and Countryside Service at Scarborough Council is responsible for many parks and green spaces and some road side verges in the Borough. We are well aware of the potential value of road verges for wildlife especially pollinating insects and we are actively exploring ways to enhance biodiversity in grass areas through changes to cutting regimes and equipment.
At the same time our local taxpayers are often vocal about grass cutting and expect a particular level of tidiness and verge management to make a good visual impression for residents and visitors. Some are also supportive of the biodiversity and pollinator agenda, but sadly we often receive more calls complaining about uncut grass areas than those declaring over-zealous mowing.
Many of the highways verges, also called the ‘soft estate’, of the county are in any case in the hands of North Yorkshire County Council or the Highways Agency (or contractors working for them). I know that these concerns have been raised with NYCC by a number of people, not least those of us working in ecology and biodiversity at local government level.
Answers are not always as simple as we would hope. To illustrate this I would set out some of the many and complex considerations. (Take a deep breath, it turns out to be quite a list.)
- Many verges are mown for road safety purposes and visibility splays around junctions. This much is difficult to dismiss as often there are legal requirements to comply with.
- Some are indeed ‘unimproved’ grassland sites with good flora and potential for enhanced management to encourage this but a blanket decision to stop cutting verges in spring and summer is not always the most ecologically beneficial, despite what one might assume.
- Some very high value verge sites in the County are recognised as such and additional investment put into managing them accordingly. Equally there are nutrient rich verges which would develop coarse vegetation of more limited value if left un-managed.
- Newer, enlightened road schemes, especially Highways Agency projects form new verges from low-nutrient subsoil, seeded with grass and wildflower mixes. Stripping off the richer topsoil is important here, but it still needs aftercare and patience while the sward establishes and competitive weeds need to be controlled. All this costs more money.
- Some North Yorkshire authorities, including SBC, have designated Sites of Importance for Nature Conservation (SINCs) on qualifying roadside grassland (typically old, botanically diverse verges which have never been ploughed, never been fertilised and always been cut or possibly grazed in the past). Others recognise ‘Special Interest Verges’ perhaps through an externally funded project officer. SBC would like to do more work in identifying more of these areas, but resources are limited.
- Reducing cutting frequency may require new machinery, capable of mowing thicker swards. The ‘arisings’ from mowing taller vegetation, if left in situ, will smother the botanical interest anyway.
- Removing arisings requires specialist machinery and additional labour, which local authorities often do not have available. The grass removed has to be disposed of too, an added expense.
- Grazing – an option on farmland is very rarely possible for roadside sites, for obvious practical reasons. It can be excellent in tandem with hay-making for managing meadow grassland away from roads, but for most Local Authorities it is just not feasible except in partnership with local farmers or possibly a Wildlife Trust etc. (Some grasslands in SBC ownership used to be managed by arrangement with farmers who could make and take hay for us, but even when offered it for free, most have very real safety concerns – sites are usually public spaces, with dog mess, litter or public liability issues – or they are simply too steep.
- Nationally a handful of Local Authorities are developing the potential for grass cuttings to be collected as feedstock for bio-digesters, offsetting the costs of management and providing renewable energy sources, but this takes time and investment to develop plus new infrastructure. Where successful this could work hand in hand with longer interval mowing and ‘cut and remove’ objectives.
- Scarborough Borough Council recently invested in newer mowing machinery (our fleet of ‘Toro’ ride-on mowers) which can cope with longer swards, yet still leave an acceptable finish, allowing us to contemplate some longer intervals between cuts in general purpose amenity grass areas. We presently have some sites where we are trialling fewer cuts in the season. Such as Burr Bank, on Scarborough’s South Bay and the bankings north of New Bridge in Whitby.
- We have also begun using a special remote controlled mower for intricate sites or for slopes too steep for ride-on mowers. This tracked machine, called the ‘Spider Mower’ copes with quite coarse vegetation is very manoeoverable and has a motorised safety winch to secure it on steep slopes. I have mentioned the use of this device before for our North Bay orchid terrace in Scarborough.
- Recent research by Plantlife (results of their citizen science data from 2019) has shown, surprisingly, that mown grassland such as garden lawns will produce the highest nectar provision with a monthly mowing frequency and nectar flower abundance declines with grass left for longer. However higher botanical diversity is associated with longer mowing intervals such as once a year, at the expense of the overall quantity of nectar per square metre.
These sorts of considerations have to be weighed up, preferably site by site, so if it’s botanical interest on verges that you are after, then a late summer ‘cut and remove’ may be ecologically the ideal but, on the downside, expensive and not universally popular in urban or sub-urban areas. In contrast for amenity grass which is relatively improved and has lower floral diversity, the best interests of pollinators may be served by a range of mowing heights and frequencies, but the optimum nectar might be found by letting clovers, dandelions, daisies, self-heal and other ‘short-grass’ species flower, which ironically will decline if the grass is left for too long. (Just as surely as wildflower numbers are reduced by mowing too often!)
I would love to devote more of my time as the Borough Ecologist to this but in practice one could do with a full-time Project Officer promoting pollinator-friendly projects and road verge management. Certainly one way to help is to a) support campaigns of Plantlife and other charities in this realm, b) support your local Wildlife Trust (YWT) and encourage them to develop road verge initiatives and c) petition your local Councillors, both in the Parish and Borough or County level, so that they are aware how important this is to you, as a voting, tax-paying resident and indicate that you would support more resource invested in developing these new practices.