Damage to beech woodlands in the Chilterns by the grey squirrel

Selective bark-stripping of beech, Fagus sylvatica, by free-ranging horses

“…Moose (Alces alces) also highly prefer coniferous species, especially Pinus sylvestris (Bergqvist et al, 2001;Faber, 1996). Grey squirrels preferentially select beech and sycamore (Acer pseudoplatanus) for bark-stripping (Mountford, 1997;Rayden and Savill, 2004;Rowe, 1984). For horses no information on bark preference is available in literature.…”

Long-term patterns and impacts of grey squirrel debarking in Lady Park Wood young-growth stands (UK)

“…MacKinnon, 1976;Rowe and Gill, 1985;Kenward and Parish, 1986;Kenward et al, 1988aKenward et al, ,b, 1992Kenward, 1989;Rayden and Savill, 2004), which have also found that vigorous beech individuals of similar sizes/ages are particularly susceptible to debarking, especially if they are growing in stands with high average phloem levels, that have been recently thinned, contain a high density of juvenile squirrels and a mixture of seed-bearing trees. Records made in the old-growth stands within Lady Park Wood support these findings: vulnerable sized beech trees here have suffered little debarking because they are suppressed and growing slowly (Mountford, 1997).…”

“…It has been suggested that beech is selected because it has a thin bark (e.g. Kenward et al, 1988b;Rayden and Savill, 2004). This can be easily said of various other species in the mixed young-growth stands at Lady Park Wood, yet only beech has been attacked on a major scale.…”

“…The lessons learnt from Lady Park Wood and elsewhere in Britain therefore have a broader applicability. Despite considerable efforts to control grey squirrel populations by poisoning, shooting and trapping (see Huxley, 2003), they have spread widely across Britain and debarking damage continues to escalate (see Rayden and Savill, 2004). Poison hoppers have admittedly been shown to be effective elsewhere, though this has required a sustained effort and incurred costs Gurnell and Pepper, 1998).…”

“…A recent estimate of damage in the Chilterns, an important forest region in southern England, found that 54% of beech and 44% of sycamore trees had some evidence of squirrel damage (Rayden and Savill, 2004). Another recent assessment of valuable broadleaved woodland in southern Britain found 100% of sycamore trees, 66% of beech, and 40% of oak Quercus petraea (Mattuschka) Lieblein, Q. robur L. had been debarked (Huxley, 2003).…”