Why hedgerows are so vital - to our countryside, our natural world and our planet

Hedgerows, better known as the woody walls that delineate our fields, roads and gardens, have been a common sight among the British landscape for centuries. Yet, despite being characteristic of our cherished countryside, these humble structures are often overlooked for the seemingly endless array of useful services they provide humans and the wider environment.

From combatting soil erosion to slowing global warming, hedgerows certainly have much more to offer than picturesque postcards or lines on a map!

An important role in agriculture

Hedgerows have long been used in both urban and rural settings to partition land and mark common routes. Being much larger and more rugged than their urban counterparts, rural hedgerows offer a particularly practical means of separating farmland fields and the crops or livestock within them. Furthermore, they are set apart from their man-made rivals, such as fences or stone walls, by the abundance of indirect benefits which arise from their impressive and complex structure.

For example, hedgerows are typically taller and thicker than fences and walls, and even though not as dense, are still extremely effective in protecting livestock and crops from harsh winds. This not only means that hedgerows provide animals with a perfect place to shelter during unpleasant weather conditions, but also reduces wind-driven soil erosion – a growing concern within the agricultural sector.

Farmers also benefit from planting and maintaining hedgerows in the face of troublesome insect pests. For example, aphids are a widespread threat to many vegetable and grain crops across the UK, owing to their insatiable appetites and the fatal viruses they transmit between plants. Yet, by planting hedgerows around affected fields, farmers can attract many insect-eating birds, flies and wasps who waste no time in devouring pesky aphids, saving valuable crops and pest control fees in the process. This makes the growing crops much more efficient and cost effective.

Crucially, hedgerows harbour great value in attracting pollinators, the backbone of food security. By providing a reliable and long-term habitat for pollinators such as wild bees, hedgerows contribute to enhancing year-on-year yields of pollination-dependent crops, thus saving farmers the time, energy and stress associated with artificial pollination.

Hedgerows also make life easier for struggling game birds such as pheasants and partridges whose stout bodies make them prime targets for cunning predators. These birds make good use of hedges as a means of seamlessly traversing across farms without the added risk of crossing flat, exposed fields. Hedgerows could therefore be key to saving these staple British birds from extinction.

An integral facilitator in our natural world 

Being a structurally complex matrix of trunks, branches and foliage, hedgerows are strong magnets for countless specialist species whose food and shelter preferences are left unfulfilled by the more simplistic surrounding fields. In fact, many of the animals we would consider to be characteristic of the countryside, such as songbirds, bats and dormice actually depend on hedgerows where the landscape is dominated by fields.

These species relish the wide range of berries, nuts, leaves, dead wood and insects concentrated within hedgerows, while also choosing to sleep, travel or even hibernate under the safety of the hedge’s branches. Hedgerows are also key to the navigation of some populations with bats, badgers and butterflies being found to especially rely on these linear structures to navigate the otherwise disorientating countryside.

However, it’s not just animals who thrive among hedgerows. Studies have found thousands of species of plants, fungi and microorganisms to inhabit these structures, with some noting the diversity of species within a given area of hedgerow to exceed that of forests. This high diversity of species can be attributed to the fact that hedgerows offer many different types of food and micro-habitats while simultaneously serving as a direct corridor connecting numerous fragmented habitats such as crop fields, pasturelands and woodlands. This helps connect struggling populations of plants and animals, allowing an exchange of genetic information which helps species to continuously adapt to their changing surroundings.

How hedgerows help our planet

One undeniably useful benefit of planting hedgerows is their ability to protect the environment from human-caused pressures. One such example is air and water pollution, both of which have become increasingly prevalent across natural landscapes owing to the growing use of road vehicles, industrial chemicals and agricultural fertilisers. Being closer to breathing height than trees, hedgerows have been found to be much more efficient than trees in filtering harmful pollutants from the air, making them a valuable asset to minimising the negative health effects of creating more roads across the country. As for water pollution, hedgerows serve as a natural barrier to surface runoff, meaning they can trap and filter heavily polluted water as it trickles across the sediment surface before it contaminates our already-struggling waterways.

This same filtration process applies to larger-scale movements of water, such as when rivers overflow during heavy rainfall. Hedges, along with other components of hedgerows such as trees or ditches, present many obstacles across the soil surface such as stems, fallen leaves, and trunks, slowing the speed at which water is spreading across land and providing an opportunity for soil, plants, and fungi to absorb some excess liquid. This same process is being increasingly recognised for its potential in urban areas where the ground is predominantly paved over with impermeable concrete, presenting a major disruption when drainage systems become overwhelmed.

One increasingly vital advantage of hedgerows, and perhaps the most overlooked, is the absorption of carbon dioxide as a primary ingredient for photosynthesis. This process, ultimately releasing oxygen as a by-product, is not only fundamental to life on Earth but could also play a key role in protecting life for decades to come. It goes without saying that excess carbon dioxide emissions are a key driver of global warming and that any means of lowering carbon dioxide levels is vital to returning to a predictable and self-regulating climate. Since hedgerows can store significant amounts of carbon in their stems, leaves and the surrounding soil, which in some cases exceeds that of equivalent areas of forests, these structures are clearly a valuable asset as governments globally look for pragmatic and cost-effective solutions to the ongoing climate crisis.

Hedgerows – the unsung hero of the countryside

All in all, there are plenty of reasons why hedgerows are a valuable asset across both rural and urban landscapes. Hedgerows provide services which benefit everyone and protect the cherished species of our ever-changing countryside. That’s why CPRE Hampshire are working hard to restore healthy hedgerows across Hampshire.

For more information and resources, visit our Hedgerow Information Hub.