One of the regular winter tasks undertaken across the Heath by the conservation team is the planting and management of our hedgerows.

Ham & High: A Hampstead Heath hedgerowA Hampstead Heath hedgerow (Image: Archant)

But how do we define a hedgerow?

One definition could be a line of managed trees and shrubs , that is to say, trees that due to the intervention of man are prohibited from reaching their natural eventual height, width and shape.

It is often perceived by people that our beloved hedgerows were mainly a result of the enclosure acts of parliament but hedgerows have been part of the British landscape for much longer than that.

With records dating back to pre-historic times and with a bonanza of planting during the Anglo Saxon period, British hedgerows have been an integral part of a working agricultural landscape since ancient times.

Defining boundaries and land ownership, (they are not easily moved by an unscrupulous land owner) hedgerows can provide a secure animal-proof barrier for livestock with the added benefit of the provision of shelter and sustenance.

With the intensification of agriculture and intervening wars our hedgerows were in acute decline toward the latter stages of the 20th century with estimates of a loss of up to 20 per cent in England between 1984 and 1990.

This situation has fortunately reversed with the aid of hedge planting grants and legislation being passed in 1997 to protect these valuable assets.

Neglect causes unmanaged hedgerows to develop into lines of mature trees or shrubs which eventually fall leaving large gaps.

Conversely over-managed hedges that are cut annually using mechanical cutters, can in time form a bottomless mushroom shape and slowly die out.

This frequent cutting often does not allow any flowers and subsequent berries to develop or persist during the winter which is detrimental to many overwintering animals.

The Heath’s conservation team have been replanting and restoring many of the Heaths historic hedge lines for a number of years now, using historical maps, planting a varied range of species which are allowed to flower and bear fruit in turn supporting a wide spectrum of wildlife.

We often incorporate additional plants such as the climbers, dog rose and honeysuckle.

Where appropriate rare trees like the wild service tree and more recently elm trees which have been shown to be resistant to Dutch elm disease can be an interesting addition. If space and conditions allow, the base of the newly planted hedge is sometimes sown with a special wild flower mix specifically for hedgerows. This adds variety, interest and benefits wildlife.

A historical technique that we often use to manage hedgerows is called hedge laying.

This involves partially cutting the stem or trunk of a bush or young tree near to ground level and laying the top over at an angle.

Although this initially looks like a harsh treatment it very rarely kills the plant and it will put on a flush of rapid growth the following spring and summer.

We often use wooden poles or binders to weave into the laid hedge to add support. These are cut from our routinely coppiced Hazel woodland which is adjacent to Hampstead Lane.