Information and Advisory Note Number 139                        Back to menu

NATURAL HERITAGE TRENDS Forest and woodland: native woodland

1. Native woodland

1.1 Native tree species generally have greater value for biodiversity than recently introduced ones, which have not developed associations with other native plant and animal species to the same degree.

1.2 The term 'native woodland' refers to stands of native trees and shrubs, the ground flora which develops under them, and the invertebrates and other animals which live in them. It is an ecological community of plants and animals that comprises an important and species rich component of Scotland's biodiversity.

1.3 Scotland's native woodland has been classified into six broad vegetation types (Figure 1). Four have been identified as 'priority habitats' in the UK Biodiversity Action Plan. The other two, lowland mixed broadleaves and upland birchwoods, have been proposed as priority habitats.

1.4 Lowland wood-pasture and parkland, a land use type found within some of the vegetation types, is also a priority habitat.

1.5 Within the UK, upland birchwoods and native pinewoods are restricted to Scotland. Also in Scotland are the best developed examples of upland oakwood, a woodland type of international importance because of its extent and the richness of its lower plant communities.



Figure 1. The composition of native woodland - a tentative assessment (MacKenzie, 1999).

2. Trends

2.1 Pre-1984

2.1.1 Prior to the 20th century, Scotland's woodland was dominated by native trees (Figure 2). Some exotic species (chiefly beech and sycamore in the lowlands, and larch in the uplands) had been planted widely, and colonised some naturally established woods (Walker & Kirby, 1989).



Figure 2. Woodland cover 1871 to 2000

2.1.2 During the First and Second World Wars, many woods were felled. In order to quickly replenish timber reserves, fast-growing, non-native conifers, such as Sitka spruce, were widely planted.

2.1.3 At the end of the Second World War, less than two-fifths of woodland in the Lowlands was composed of native species. In the Highlands they still accounted for two-thirds of the woodland cover (MacKenzie & Callander, 1995, 1996).

2.1.4 In the decades that followed, many native woods were cleared or under-planted with conifers. By the mid-1980s, 30-50% of native woodland had been lost. By then, it comprised only 10% of all woodland in the Lowlands and one-third in the Highlands (MacKenzie & Callander, 1995, 1996).

2.2 1984-1999

2.2.1 Since the Forestry Commission Broadleaves Policy 1985, the decline of native woodland has been arrested and reversed.

2.2.2 Tax relief for new planting, which had driven the plantation of exotic conifers, ceased in 1988. The Woodland Grant Scheme, introduced the same year, increased grant aid for the establishment of broadleaves and native pinewoods.

2.2.3 In 1999, 'native' species made up nearly a quarter (23% or 3,209 km²) of Scotland's woodland (Figure 3), an increase of 34% since 1984.

2.2.4 Around half (53%) of this was originally planted, and the rest had established by natural regeneration.

2.2.5 Half (1,593 km²) was broadleaves, a 40% increase since 1984. However, this underestimates the true area of native broadleaves, as it does not include 'Mixed and other broadleaves'. The proportion of native species in this category is unknown.



Figure 3. Woodland composition in 1999

3. Native pinewoods

3.1 Native pinewoods in the UK are restricted to the Highlands of Scotland (Figure 4). In prehistoric times they may have extended over 15,000 km2 (UK Steering Group, 1995), but have subsequently been reduced to a small fraction of that area. Of international importance, remnant native pinewoods are classed as a 'priority habitat' in the UK Biodiversity Action Plan and also a priority habitat (as Caledonian Forest) on Annex I of the EU Habitats Directive.

3.2 Some rare and uncommon species associated with native pinewoods include twinflower, capercaillie, and the Caledonian sac spider. Britain's only endemic bird, the Scottish crossbill, is dependent on native pinewoods.

3.3 Many pinewoods are sparsely wooded, with regeneration suppressed by the heavy browsing of deer and sheep.

3.4 This sparse canopy cover has complicated estimation of the extent of this habitat. There are also difficulties in defining what constitutes a 'native' pinewood.

3.5 In 1999, the total area of woodland dominated by Scots pine was estimated to be 1,616 km². This represented a 28% increase since 1984,  80% (1,362 km²) had been planted (MacKenzie, 1999), and much was derived from non-native varieties and managed primarily for timber production.



Figure 4. The distribution of native pinewoods (1998) (Source: Forestry Commission)

3.6 The 1998 Caledonian Pinewood Inventory lists 180 km2 of woodland that is believed to be descended from the original Caledonian pine forest which spread over mainland Scotland after the last ice-age (Jones, 1999).

4. Trends

4.1 Trends from 1989 to 1998 (Figure 5)

4.1.1 In 1989, grants for establishing new native pinewoods became available through the new Woodland Grant Scheme (WGS). Prior to this, a premium rate of grant had been available through the previous schemes.

• By 1994, grants for 203 schemes had been approved. Although 70 were smaller than 20 ha in size, 75% of the woodland established was in schemes of 100 ha or more and 50% was in schemes larger than 250 ha.
• In total, 275 km2 native pinewood was established through the WGS between 1990 and 1998.
·Between 1994 and 1998, Scots pine accounted for more than 50% of all conifers established annually under the WGS in the Forestry Commission's Highland Conservancy.
·The area of native pinewood on Forest Enterprise (FE) land in the Highlands remained constant between 1988 and 1997. As planting of exotic conifers decreased, the proportion of native Scots pine increased from 4% of all conifers planted in FE's North Scotland Region in 1988 to 15% in 1997.
·The restoration of the 40 km2 of native pine woodland on FE's estate, by the removal of non-native trees and protection of woods from deer, began in 1992. By 1994, a quarter of the area had been cleared of non-native trees.



Figure 5. Annual planting of native pinewood, grant aided and planted on Forest Enterprise and, from 1989/90 to 1997/98