Figure 5 Veteran trees from former woodlands growing in planted conifer forests; sudden exposure through clearfelling may result in the death of these trees and halo thinning would be an appropriate management option here.
Old stools Old stools can comprise both overstorey trees and understorey shrubs. They will often derive from previously coppiced trees but may also have arisen from trees which survived ring-barking. Such trees may be of local genotype. They may have some features in common with veterans (e.g. standing deadwood, epiphytes, niches for rare invertebrates) and the potential to provide seed for regeneration and structural habitat for woodland species. The presence of old coppice stools will influence management. For example, their crowns are often small and careful thinning on several occasions may be needed to promote crown development and seed production. They may be unstable (Figure 6) and collapse if thinning is too heavy, and they may not resprout from the stools if they are felled. Stools and stems can also be very valuable for deadwood invertebrates and epiphytes. Felling of stems should be avoided if possible.
Figure 6 Coppice stools, such as this old ash, may be unstable due to the distribution of stems around the periphery of a central rotting core.
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