Kirsty Brown – Conservation Project Assistant
Hedgerows are an important feature of the English countryside, adding to the aesthetic value and character of the landscape around us. Data collected by the Countryside Survey 2007 indicated that there was just under 250,000 miles (402,000 km) of hedgerow in England (Countryside Survey data owned by NERC – Centre for Ecology & Hydrology). Field boundary hedges in and around the North York Moors can be of considerable wildlife value and are a living historic record of demarcation.
What’s in your hedge?
The number, variation and type of plant species in a hedgerow can point towards its age, and some hedges are remnants of ancient woodlands. Rare plants may thrive in and around the footings and ditches. Hedges support a wealth of wildlife as they provide food, shelter and nectar. Pollinators such as honey and bumble bees take full advantage of the early spring flowers of blackthorn and late-season ivy flowers. A plethora of invertebrates live within hedges, seeking out the nooks and crannies, leaves, fruit and soil. Voles, shrews and rabbits create their tunnels in a maze beneath the roots, using the thick hedge to hide from predators as they search for food. Larger mammals such as badgers and foxes also frequently live in and around hedgerows, making use of the food supply and shelter. Bats are known to use these linear features as food sources or as a commuting highway to get between the roost and feeding grounds, choosing the more sheltered side in strong winds. Birds of prey such as kestrels and owls may use the hedgerow trees as look-out posts and resting spots whilst they digest their prey. Many other species of bird use hedges throughout the year for shelter, nesting and roosting sites.
Mycorrhizal fungi are associated with hedgerows and boundary trees. Mycorrhizae are found between plant roots and the soil, helping plants gather the moisture and nutrients (such as phosphorus) that they need in exchange for carbohydrates and sugars in a mutualistic relationship. Root diseases also appear to be reduced in presence of mycorrhizae. The mycorrhizae and fungi effectively extend the root system, and it has been said that a single oak tree might have up to 19 km of mycelium associated with it! Cultivation and the application of fertilisers can supress and disrupt this beneficial underground network. For more information – the BBC recently produced an article on these connections, describing how plants can even communicate aphid attacks.
Hedges criss-cross the landscape and form important habitat connections for wildlife, allowing greater freedom of movement between different habitat ‘islands’. Our Connectivity programme looks to develop these habitat connections, and other organisations have similar projects such as the Wildlife Trusts’ Living Landscapes. These efforts stem from the Government’s Natural Environment White Paper.