Appendix 2: the National Vegetation Classification
The NVC is a phytosociological classification (i.e. one based on the distinctive combinations of plant species which develop under particular conditions) which describes nineteen woodland and six scrub communities (Rodwell 1991). These communities are associated with different habitats, described in terms of climatic zone, soil types, terrain and topographic position. These relationships are described in varying degree of complexity and detail by Rodwell (1991), Rodwell & Patterson (1994) and Pyatt (1995). The NVC woodland types used in this project are:
- W4 Birch woodland with purple moor grass
- W6 Alder woodland with stinging nettle
- W7 Alder – ash woodland with yellow pimpernel
- W8 Lowland mixed broadleaved woodland with dog’s mercury
- W9 Upland mixed broadleaved woodland with dog’s mercury
- W10 Lowland mixed broadleaved woodland with bluebell/wild hyacinth
- W11 Upland oak – birch woodland with bluebell/wild hyacinth
- W17 Upland oak – birch woodland with blaeberry
- W18 Scots pine woodland with heather
- W19 Juniper woodland with wood sorrel
For the purposes of the current project, two situations required particular consideration:
- NVC coverage of the sub-alpine scrub zone is poor, so McVean & Ratcliffe (1962) has been used to identify a range of montane scrub categories.
- The distribution of W4, according to Rodwell (1991), is biased towards flushed peaty gleys and the margins of basin peats in the south and east of the UK. However, according to Rodwell & Patterson (1994), this is the only possible NVC option on the extensive wet moorland of upland Scotland.
Table 3 lists all the woodland types used by the NWM
Table 3: Woodland types used by the NWM
| Code | Definition |
| U | Unsuitable for tree/scrub growth |
| DR | Developed rural land |
| BU | Built-up land |
| Water | Inland Water |
| W8 | W8 Lowland mixed broadleaved with dog’s mercury |
| W8/W7 | W8 + W7 Mosaic |
| W10 | W10 Lowland mixed broadleaved with bluebell/wild hyacinth |
| W10/W7 | W10 + W7 Mosaic |
| W10/W8 | W10/W8 |
| W10/W7 | W10/W7 |
| W9 | W9 Upland mixed broadleaved with dog’s mercury |
| W9/W11 | W9/W11 |
| W9/W7 | W9 + W7 Mosaic |
| W11 | W11 Upland Oak-Birch with bluebell/wild hyacinth |
| W11/W4 | W11 + W4 Mosaic |
| W11/W17 | W11/W17 |
| W11/W7 | W11 + W7 Mosaic |
| W11/W9 | W11/W9 |
| W11/W7 | W11/W7 |
| W11/Sc6 | W11 + basin bog woodland/scrub mosaic |
| W17 | W17 Upland Oak-Birch with bilberry/blaeberry |
| W17/W4 | W17 + W4 Mosaic |
| W17/W18 | W17/W18 |
| W17/W11 | W17/W11 |
| W17/W18/W4 | W17/W18 + W4 Birch (with open ground) Mosaic |
| W6 | W6 Alder with stinging nettle |
| W6/W11 | W6 + W11 Mosaic |
| W4 | W4 Birch with purple moor grass & open ground |
| W4/W6 | W4 + W6 Mosaic |
| W4/W17 | W4 + W17 Mosaic |
| W4/W18 | W4 + W18 Mosaic |
| W4a | W4 Birch with purple moor grass |
| W4/Sc5/W17/W18 | W4 Birch (with open ground) + Peatland with scattered trees/scrub + W17/W18 Mosaic |
| W4/W17/W18 | W4 Birch (with open ground) + W17/W18 Mosaic |
| W4/Sc5 | W4 Birch (with open ground)+ Peatland with scattered trees/scrub mosaic |
| W7 | W7 Alder-ash with yellow pimpernel |
| W7/W4 | W7 + W4 Mosaic |
| W7/Sc5 | W7 + Peatland with scattered trees/scrub mosaic |
| W7/W17 | W7 + W17 Mosaic |
| W7/W11 | W7 + W11 Mosaic |
| W7/W9 | W7 + W9 Mosaic |
| W7/W11 | W7/W11 |
| W7/W10 | W7/W10 |
| W18 | W18 Scots Pine with heather |
| W18/W4 | W18 + W4 Mosaic |
| W18/W11 | W18 + W11 Mosaic |
| W18/W17 | W18/W17 |
| W18/W4/Sc5 | W18 + W4 + Peatland with scattered trees/scrub Mosaic |
| W18/Sc5 | W18 + Peatland with scattered trees/scrub Mosaic |
| W19 | W19 Juniper woodland with wood sorrel |
| Sc5/W18 | Peatland with scattered trees/scrub + W18 Mosaic |
| Sc6/W11 | Basin Bog woodland/scrub + W11 |
| Sc1 | Juniper |
| Sc2 | Scattered Juniper |
| Sc3 | Birch/Willow |
| Sc4 | Scattered Birch/Willow |
| Sc5 | Peatland with scattered trees/scrub |
| Sc6 | Basin Bog woodland/scrub |
| Sc5/W4/W17/W18 | Peatland with scattered trees/scrub + W4 Birch with purple moor grass and open ground + W17/W18 Mosaic |
| Sc5/W4 | Peatland with scattered trees/scrub + W4 Birch with purple moor grass and open ground mosaic |
| Sc7 | Mixed montane scrub |
| Sc8 | Scattered mixed montane scrub |