Effects of clear-felling versus gradual removal of conifer trees on the survival of understorey plants during the restoration of ancient woodlands

Abstract

a b s t r a c tPlantations of exotic conifers on ancient woodland sites retain many features of high conservation value and in many countries such sites are being actively restored. Clear-felling of the conifer trees is often a straight-forward first step, but recent guidance on restoration advocates gradual removal of the plantation crop to protect vulnerable woodland specialist plants. To date there has been little empirical evidence to support this policy. One hundred and four stands in 39 woodland sites in the UK owned by the Woodland Trust from Cornwall to Invernesshire were surveyed in 2001 and again in 2009 to assess the survival of woodland flora following restoration by both clear-felling and gradual removal of the plantation crop. On average, there were over seven woodland specialist and ancient woodland indicator species in each of the stands surveyed. Loss of specialist woodland species -the most shade adapted component of the flora -over this time period was strongly correlated with the degree of canopy opening. In contrast, the loss of more light demanding plant species was not related to the intensity of tree removals. This study suggests that a careful assessment and prioritisation of conservation values is needed before restoration. Rapid removal of an exotic species as part of a restoration programme may have an adverse effect on subsequent succession.

Long-term changes in the flora of oak forests and of oak:spruce mixtures following removal of conifers

“…There was no indication that the richness of Woodland specialists, as defined by , were adversely affected by opening the canopy in contrast to the findings of Brown et al (2015). The latter used a different definition of specialist plant but at Salcey their species, as a group, tended to do slightly better (and certainly no worse) than either the flora as a whole or Woodland specialists as defined in this study ( Supplementary Table S.1).…”

“…Plant Strategy Types (Grime et al, 2007) were also noted ( Supplementary Table S1) but no clear patterns emerged with respect to these. Brown et al (2015) used a different definition of specialist plants, although in terms of the species found in Salcey Forest most of their species are also in the Woodland specialist list ( Supplementary Table S1).…”

“…and Douglas-fir (Pseudotsuga menzii (Mirbel) Franco). Brown et al (2015) similarly noted some loss of species even where stands were restored to native broadleaves gradually and concluded that specialist plants were particularly affected. Godefroid et al (2005) found that some forest species (such as Carex remota, Circaea lutetiana, Dryopteris dilatata, Oxalis acetosella) declined in clear-cuts in old beech high forest in Belgium.…”

Global guidelines for the sustainable use of non-native trees to prevent tree invasions and mitigate their negative impacts

“…Specific guidelines for restoration of sites previously occupied by planted forests of R. pseudoacacia have been produced in the Piedmont region of Italy and in China (Zhang et al 2018). Sturgess and Atkinson (1993) suggested management strategies for the restoration of near-natural sand dune habitats following the clearfelling of Pinus planted forests in Britain, and Brown et al (2015) proposed approaches for restoring areas previously planted with non-native conifers on ancient woodland sites. Szitár et al (2014) assessed the recovery of open and closed grasslands over five years after the removal of planted forests of non-native pine species through burning in an inland sand dune system in Hungary.…”

Soil Properties in Two Forest Sites in Cox's Bazar, Bangladesh

“…Shukla et al (2014) reported that Shannon-Wiener index of a reserve forest in eastern Himalayas in India was 4.77. Brown et al (2015) reported that clear-felling created a 리 ush of vigorous plant growth, this was not long-lasting, and the end result was reduced plant biodiversity.…”