This weekend the Sutton Nature teamed up with a group of young people from The Challenge, an organisation designed to encourage young people to challenge themselves and try new things. The team were out at Roundshaw Downs, carrying out blackthorn (Prunus spinosa) scalloping on the hedgeline at the far-end on the reserve.

Challenge 2

Getting stuck into cutting back the blackthorn hedgeline

Hedgelines are an important habitat for wildlife and provide food such as nectar and berries, as well as shelter and nesting sites for invertebrates, small mammals and birds. At Roundshaw Downs, the SNCV maintains and manages the blackthorn hedgeline for wildlife, which involves regularly cutting back or “scalloping.” Scalloping is a technique that involves removing large semicircular sections from the existing mature hedge. By cutting areas of the hedge in this shape, it actually extends the overall length of the hedge and makes seeds and fruit more accessible to foraging birds and mammals, as well as providing more shelter.

Scalloping also helps create a diversity of age, structure and species along the hedge. Removing some of the blackthorn encourages new growth and a variety of scrub height for different species to exploit. The bare earth that becomes immediately exposed after cutting, provides a warm sheltered area (microclimates) for basking invertebrates and reptiles.

Brown Hairstreak eggs laid on a young blackthorn branch © Dave Wilton

Crucially, one of the main reasons why the SNCV carries out blackthorn scalloping at Roundshaw is to provide greater habitat for the elusive Brown Hairstreak butterfly (Thecla betulae). The Brown Hairstreak uses young blackthorn branches to lay its eggs on, these eggs then hatch into caterpillars which feed of blackthorn leaves. As an adult the Brown Hairstreak will spend much of its time high up in the tree-tops feeding on aphid honeydew or attempting to attract a mate. This rather secretive butterfly has experienced dramatic declines, however, over the past few decades and is currently a Priority Species in the UK Biodiversity Action Plan.

Brown hairstreak female

Its decline has mainly been due to the loss of hedgerows across the country, which is why managing the hedgeline to encourage young blackthorn growth is so important, to help protect this species from further declines.

The work that the young people helped the SNCV with on Saturday was a great step towards maintaining a good quality blackthorn hedgeline habitat for the Brown Hairstreak and many other invertebrates, birds and mammals. Good work guys!

The finished result of scalloping

The finished result

Eleanor Kirby-Green

SNCV Biodiversity Assistant

Become a volunteer
Sutton nature events