Hedgerows are an intrinsic part of our landscape and in many places owe their existence to the need to divide grassland into conveniently-sized grazing pastures for livestock or to define ownership boundaries.
Hedgerows provide excellent natural weather barriers and habitat for wildlife, but also perform a natural flood management (NFM) function by intercepting rainfall, slowing overland runoff and increasing infiltration. Planting hedgerows on small embankments, known as kested hedgerows, can improve the growth of the hedge and enhance the NFM and water quality benefit by intercepting and temporarily storing overland flow.
These benefits can be achieved by planting new hedgerows across slopes, or restoring old hedgerow boundaries still evident in the landscape.
How they work
Hedgerows can provide a natural physical barrier that slows the flow of overland runoff, reducing the amount of sediment and diffuse pollution (run-off from land containing pollutants) reaching the river. Having this planted area increases the interception and absorption of rainfall and prevents soil, sediment and nutrient loss from fields. They reduce soil erosion by protecting the soil and crops from the full force of strong winds and rain. Increased leaf litter improves soil quality.
Hedgerows not only protect crops, they provide shelter and shade for livestock. How often have you noticed sheep huddling against a hedge in poor weather? Evidence suggests that this can lower lamb mortality. They also provide welcome habitat for birds and beneficial insects, including pollinators and predators of pests.
Long term, the maintenance costs of hedgerows are low, but whilst they are establishing themselves they need annual maintenance, and weeds such as brambles need to be kept at bay. Hedgerows require fencing to eliminate livestock access and therefore allow the hedges to grow, the fencing may require small amounts of maintenance.
Our volunteers have planted miles of hedgerows throughout the catchment. We tend to plant hedgerows with a combination of species, such as Hazel, Blackthorn, Hawthorn, Beech, Rose and Ash to provide a variety of habitat and feed sources for birds and other wildlife. Over the past year we have planted some cross slope hedgerows on Mell Fell as we are interested in the potential NFM benefits that cross slope hedgerows can offer in slowing the flow of water on steep slopes so that it increases the time taken to reach the river during heavy rainfall – potentially reducing the timing of the river’s flood peak.
Funding mainly comes from agri-environment schemes such as Natural England’s Countryside Stewardship scheme and, if restoring existing hedges, from their Hedgerows and Boundaries grant scheme.
How you can help
If you are a farmer/landowner interested creating hedgerows, especially cross slope ones, read the Natural Flood Management Measures: A guide for Farmers hand book. If you are in one of our Facilitation Fund Farmers groups, get in touch with our Farming and Conservation team for an informal chat about their suitability on your land.