Love Your Scrub is a project being managed by Rewilding Sussex for the University of Sussex to expand scrub habitat on the university campus. Increasing biodiversity is its main aim, but it is also seeking to promote an awareness of scrub as a habitat and how time spent within and around it can help human wellbeing too.
If this sounds exciting and you would like to be a part of it, Rewilding Sussex welcomes volunteers, both from the university and elsewhere. We will be working with academics and students from a variety of disciplines, but you do not need to be either, you just need to Love Your Scrub!
What is scrub?
Scrub is a habitat made up of woody, often thorny shrubs or small trees such as hawthorn and blackthorn, hazel and spindle, bramble, dogwood and dog rose. It can act as a nursery for sapling trees, such as birch and beech, oak and ash, the thorny thickets around them providing protection from browsing herbivores, such as deer. Its margins, and the clearings within it, may support a range of herbaceous plants less suited to open grassland while its briars and tangled branches provide a haven for nesting birds, small mammals, numerous beetles, moths and other invertebrates and even the odd reptile.
Scrub may develop from grassland, perhaps where grazing animals have been removed for a time and there has been no mowing or cutting but, over a time scale of years, it is a transitory environment: the plants which make it up will change and it will in many cases ultimately give way to woodland unless something, whether human or animal, intervenes.
Why is scrub important for biodiversity?
Scrub is a feature of many different environments, ranging from low-lying coastal wetlands to uplands, encompassing heathlands, grasslands and fens. Many species of conservation importance in the UK are associated with scrub habitat, including 44 nationally scarce plant species, 281 rare, vulnerable or endangered insects, and 39 birds classed as priorities for conservation or of conservation concern under the Biodiversity Action Plan.
The Love Your Scrub project will be sited on chalk downland and here a mixed mosaic of scrub and grassland habitat can act to protect a diverse assemblage of herbaceous plant species which struggle to survive in open grassland where they may be grazed or cut, including bloody crane’s bill and the nationally scarce man orchid. The scrub itself provides structure for climbing plants such as traveller’s joy, honeysuckle and black bryony.
Scrub provides a food source for a large number of invertebrates, which may eat leaves, bark, fruits, flowers, nectar or dead-wood and leaf litter. Many of these are specific to certain types of scrub plant. Juniper, for example, is a rare but widespread scrubland shrub that may be found on chalk downland – 41% of the insects associated with juniper are only associated with juniper.
The invertebrate fauna is one reason why scrub is important to many bird species, particularly for feeding their young in spring, but birds also locate their nests in scrub, roost in scrub and forage for berries in late summer, autumn and winter. The bird species vary by the composition and age of scrub and by its associated neighbouring habitats, such as grassland or woodland. There were 89 separate species of bird recorded in a survey of 39 sites each having at least 50% scrub cover. Some rare but celebrated species, such as the nightingale and nightjar, are scrub-dwellers, the nightingale especially favouring dense scrub, as are yellowhammers and lesser whitethroats. Many more familiar garden songbirds, such as the song thrush, blackbird and blackcap will also nest in, and sing from, scrub. Latter-day Scandinavian raiding parties of fieldfare and redwing seek out the treasure of red hawthorn and other berries in winter.
Reptile species are far fewer in England generally and scrub specifically, but the adder, common lizard and slow worm are associated with scrub habitat. All three will burrow into leaf litter, bask in sunny open spaces and take cover or hibernate in deadwood. A mosaic of scrubland, woodland and grassland habitats are important for these animals.
Among the mammals, hedgehogs use scrub for daytime shelter and winter hibernation. They also favour scrub where it has neighbouring grassland, woodland or hedgerows for night-time foraging. Hedgehogs have been in severe decline in England for a long time and current research shows populations have fallen more in the countryside than in urban areas in recent years. Habitat loss in the countryside could be a factor. Dormice are another at-risk mammal species. They favour connected areas of diverse scrub for foraging and nest-building.
Scrub often develops in one form or another where open land is left to nature and so rewilding projects around the country are providing test cases for the benefits of scrub succession on biodiversity. Some of the results have been astonishing. Not far away in West Sussex, the Knepp estate is the most famous local example. There, they have seen dramatic improvements in local bird populations (such as nightingale, yellowhammer and lesser whitethroat), in invertebrates (including the very glamourous purple emperor butterfly) and among mammal groups, such as bats. Love Your Scrub is on a tiny scale by comparison, but every little helps!
Why does scrub need promoting?
Scrub has an image problem: it is seen as untidy and invasive. In the countryside, it is widely cleared, has been seldom promoted (until more recently, by rewilding projects in particular), and even the more acceptable, tidier face of countryside scrub – the hedgerow – is in long-term decline: 19% of hedgerows were lost between 1984 and 1990. In the built environment, it is often scrub species that are the first woody plants to colonise the kinds of derelict and decaying sites that people usually consider to be eyesores. Yet, in doing so, they can help make such places more biodiverse than much of the tidy British countryside.
Tidiness is a culturally conditioned concept for a modern human environment which has no logic in the natural world. It is not only not useful, but actually damaging for our wildlife. Creatures cannot readily live in places with hard landscaping, mown ground, vast acreages of monoculture cropland, places with fences rather than hedgerows, where the wild-grown plants are weeds to be eradicated and the insects are pests to be destroyed.
Scrub is a symbol of letting go, of releasing the shackles, of letting nature have a freer rein. There are wild things out there that desperately need it. Turn away from tidy and find the wild! Learn to Love Your Scrub!
So, what is the plan?
The University has allocated around 2 hectares (5 acres) of land on the slopes to the west of the campus, bordering woodland within the Stanmer Park nature reserve. This land is currently grassed with some sapling trees. Rewilding Sussex will agree a development plan with the University’s School of Life Sciences for the initial approach to scrub development on the site, which could mean:
- Planting some young plants
- Scattering some scrub plant seeds
- Turning over some of the surface soil to break-up the grassland sward and allow succession of scrub species
- Doing nothing and letting nature take its course
- Doing some or all of the above in different parts of the site, to compare their relative effects on scrubland succession and biodiversity over time
We plan to undertake this work between autumn 2022 and spring 2023, together with conducting initial biodiversity surveys to determine a “baseline” against which future changes to biodiversity can be measured.
Beyond the initial set-up phase, a monitoring programme will be needed and ultimately a management framework to decide what, if anything, should be done to promote and maintain a scrubland environment with increasing biodiversity as the key aim. For example, we expect rabbits to continue grazing sections of the slope, but additional action may be needed to mimic grazing by larger herbivores to promote a diverse habitat structure. We will also need to work with others inside and outside the university to develop other aspects of the project, in particular to study and promote the benefits to human wellbeing of connecting with this developing natural environment. Mother Nature has kindly agreed to do most of the work, but we need human helpers too. If this sounds like something that you would like to be involved with, please contact Rewilding Sussex here
Sources for this page:
Many of the facts and figures come from the Natural England “The Scrub Management Handbook” (2003) and from a JNCC report on which it depends heavily, “The nature conservation value of scrub in Britain” (2000). Other sources are the “State of British Hedgehogs Report 2022”, produced jointly by the British Hedgehog Preservation Society and the People’s Trust for Endangered Species; the website of the UK Centre for Ecology & Hydrology Countryside Survey (for hedgerow data); and the website of Knepp Wildland.
Written by Stephen Woodcock