# C4 Scrub
Photo: Woodlands.co.uk
# Definition of landscape category
Areas with diffused boundaries with less than 2O% cover by area of mature timber species with a rough understory of shrubs and grasses. Trees such as;
- Birch (Betula spp)
- Alder Alnus glutinosa)
- Willow (Salix spp)
- Hazel (Corylus avellana)
must be less than 3.5 m high although shrubs such as Blackthorn (Prunus spinosa) and Hawthorn (Crataegus spp) may be higher.
For this assessment no minimum mapping unit is applied.
# Aerial Definition
- Google photo sphere Hope Valley (opens new window) Looking West patches of green Gorse scrub seen on the hillside.
# In the Peak District
Many other species are included in the category and may often be dominant. In the Peak District Gorse (Ulex europæus), Broom (Cytisus scoparius), Bramble/blackberry (Rubus fructicosus agg.), Willow less than 5m tall (Salix. spp.) are components. Grey Willow taller than 5m is often included as scrub here (as in JNCC phase1 survey) but not currently in this schema as the method does not resolve species.
Much of the scrub in the Peak District is Gorse as can be seen by the dark green small bushes in the main image above. On aerial imagery gorse can be difficult to distinguish from the heather (Calluna vulgaris & Erica Cinerea); using shadows and a careful comparison of colour/structure is required although if flowering it is unmistakable (see fig. 2f & 2g). Scrub can also contain an understory of dwarf shrubs and ground flora. Scrub can occupy the transition between established woodland and other habitats as part of the structure of woodland edge vegetation and wooded pastures. If land management objectives change such as the exclusion, or reduction in densities, of grazing animals scrub will form as a transitional(seral) stage in characteristic successional or plagioclimax plant communities such as scrub pasture and woodlands given time.