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Plate 7 Coppicing on a relatively small scale provides high diversity of structure.

Woodland management for birds: Birds and woodlands in Wales

unlikely to be as valuable to birds as well- mixed stands, even if they comprise native species like hazel. Single species stands will provide less of the small-scale structural variety that comes with varying growth rates and stem densities. Meanwhile, the peak in invertebrate biomass from each tree species is relatively short, and is not synchronous, so mixed stands provide a protracted foraging window. The same applies to tree fruits.

Management

  • Woody species composition can be enhanced by encouraging those that already occur sparsely, or by planting appropriate locally indigenous species. Both techniques are relatively straightforward and will add to both structural diversity and to food availability. Where appropriate, composition can be enhanced with species that have a high invertebrate association, bear suitable fruit and/or provide good structure, eg bramble.

Issue: lack of structural diversity; short rotation coppice favours those birds that prefer younger coppice, but will limit those that use the mature stages.

Management

  • Coppice, when fully operational, should provide the full range of growth stages, all of which are used by birds. Depending on the growth rate of the woody species present, a cycle that includes ‘mature coppice’ at 10–15 years should be planned.

  • A largely dense, compact structure with early gap closure will benefit many of the birds that use coppice, by providing sheltered nest sites with some protection from predators and an abundance of safe feeding habitat.

  • Bramble, where it is allowed to develop, provides dense cover in the early growth stage – it will be largely suppressed as the coppice outgrows it so should not be a problem during harvest.

  • Suckering species such as elm, aspen or cherry contribute to a dense structure in the early growth stage. Sucker growth, depending on the species, may be suppressed with time by the more vigorous coppice growth.

  • Occasional small gaps, glades or rides are often beneficial – occasional gaps in the continuous canopy increase the volume of foliage and hence biomass of invertebrate and berry food.

  • Coppice with standards will offer more mature trees, increased species diversity and deadwood opportunities.

Issue: coupe size; large coupes are usually regarded as being commercially more viable, but have little structural variation so do not support optimum densities of birds. However, small coupes, which are more difficult to manage, do not always offer optimum habitat for all species. Birds with a relatively narrow niche might suffer if there is insufficient coppice of the right age.

Management

  • Plan coupes carefully to deliver a balance of variety and continuity.

  • Juxtapose coupes of markedly different ages to create a high structural diversity. As with gaps and rides, increased foliage is provided along the boundaries between coupes, with increased foraging opportunities.

  • Sequentially cut coupes will have less structural diversity but will not isolate age classes allowing species that need more extensive areas of similar age coppice to prosper.

  • Depending on the area of coppice available and the objectives of management, it should be possible to incorporate elements of both systems into the design to provide conditions

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