Reserve management of heathland

Dav Bridger

Ranger

Over the past 200 years Britain has lost 80% of its heathland, so it is important that what remains is conserved and enhanced, with woodland not being allowed to establish (or indeed re-establish) and trees encroach.

Our active management of our heathland reserves may seem destructive, but without it, this precious heathland habitat would decline and diminish. Healthy heathlands will benefit a range of wildlife and vegetation, in particular for ground-nesting birds such as the Nightjar.

An important feature for heathlands is negative space, ie bare ground. These patches warm up under direct sunlight and are ideal places for reptiles to bask, such as our only venomous snake, the Adder. Bare ground allows room for heather to seed and provides space for new plant growth. 

While not always ideal or wholly beneficial, sometimes having fires for our cut/removed vegetation does encourage bare ground, as well as the simple truth that removing so many swathes of cut trees and scrub being very time consuming, expensive, and generally not ergonomic. Additionally, on sites like Graffham, invasive, non-native garden escapees like Gaultheria are present and upon their removal (they must be dug up with as much root material as possible), they cannot be taken off site and for risk of dispersal to new areas. As such, burning what is cut makes for a reasonable solution.

One of the main and regular methods of heathland management is Birch popping, cutting Pine and Bracken control.

Silver Birch can be beneficial and positive for heathland wildlife in low numbers, but they fast growing trees that produce a lot of seeds that can be dispersed by wind. So they have to be 'popped' out of the ground using tree poppers, root and all, so as much of the plant is removed. If they are just simply cut they will coppice and regrow even denser. 

Pine (typically Scots Pine) can also grow quickly and tall, shading out vegetation below, making it dark, cool, and unfavourable for heather, reptiles, invertebrates and other wildlife. Pine is easier to manage, as it can be cut low to the ground. This provides areas of decaying wood for certain fungi to grow on. Additionally, removal of these trees means regaining areas of bare ground.

Bracken spreads by rhizomes, like a network of roots, deep below ground. Grazing cannot be used to manage Bracken, as it is generally unpalatable and toxic to grazing stock such as cattle, horses, ponies, sheep and goats. There doesn't seem to be a consensus on how to most effectively manage Bracken. It can be hand pulled, which is probably one of the most effective as you will pull up a portion of the rhizome along with it. We use Bracken whackers (somewhere between a scythe and a hockey stick) which will either cut right through the stem (thus stunting its growth and taking the energy out of it) or 'bruise' it, which will also stunt its growth. 

A hedge trimmer can also be used to cut through the stems in this way. Any that are cut or pulled need to be raked up and removed from the area. The main issue with Bracken is that it can grow so quickly, densely and spread widely, which shades out and outcompetes anything underneath it. Other methods of management (that the Trust don't use) would be using a horse-drawn roller, that squashes, breaks and bruises the bracken to stunt its growth.

At the Trust, we use grazing as a heathland management technique, with small groups of our Sussex Cattle. Grazing is a traditional technique that helps maintain the species richness and diversity as the cattle feed on nutrient rich plants and grasses, removing nutrients from the heathland, making it harder for invasive or undesirable plants to establish. Larger grazing animals such as cattle, horses or ponies are also good at breaking up dense areas of scrub growth as they move through the landscape. This can lead to a mosaic of different habitats that benefit all the different animals, plants and fungi that inhabit heathlands. 

In a wilder Britain, free of borders, boundaries and fence lines, large grazing and browsing animals would have been able to migrate and move through landscapes, acting as a natural heathland management.