Accounting for Nature: Assessing habitats in the UK countryside
5.   Woodlands

Conclusions

5.37 The changes in the stock and quality of Broadleaved and Coniferous Woodlands that have been recorded by the surveys in Great Britain and Northern Ireland suggest that some important environmental gains have been made during the 1990s. The stock of Broadleaved Woodland in the UK has increased by about 5% since 1990, to around 1.5 million ha in 1998. The area of Coniferous Woodland was stable over the same period, at around 1.4 million ha or 6% of the UK land area.

5.38 The expansion of Broadleaved Woodland cover is consistent with current policies to increase the area of native woodlands. However, at the annual rate of expansion recorded by CS2000, it would take about 150 years to double the current stock of Broadleaved Woodland. The expansion of Coniferous Woodland that was a feature of the post-war period, often at the expense of high quality wildlife habitat such as heath and bog, has slowed in some areas and reversed in others. CS2000 provides some evidence of conversion of these plantations to Broadleaved Woodland, especially in the lowlands.

5.39 These environmental gains must, however, be offset by some of the changes in woodland condition recorded by CS2000. There is evidence, for example, of widespread nutrient enrichment of longer established Broadleaved Woodland since 1990. Moreover, new woodland, which is now often being planted on former agricultural land, tends to have a higher nutrient status than the stock which is being lost.

5.40 The long-term implications of a general nutrient enrichment of the Broadleaved Woodland stock is unclear. The trend poses some challenging questions in the context of policies which seek to sustain and enhance the key qualities of the woodland stock. A crucial issue, for example, is whether the newer woods will become ecologically equivalent to the older woodland and, if so, over what time scales. Further work is required to determine the extent to which recently planted woodlands compensate for those that have in the past been lost.

5.41 The analysis of the vegetation data for the Coniferous Woodland Broad Habitat provides no clear evidence that the structure of these plantations is becoming more diverse. Moreover, there appears to have been a continuing loss of the Broadleaved Woodland, Dwarf Shrub Heath and Bog Broad Habitats to Coniferous Woodland. It may be too early to detect the effects of recent changes in forestry policy in these data.