Synonymy

Scottish Calluna heath Smith 1911, Tansley 1939 p.p.; Callunetum vulgaris McVean & Ratcliffe 1962 p.p., Birks 1973, Prentice & Prentice 1975, Meek 1975, 1976, Evans et al. 1977p.p., Hill & Evans 1978, Ferreira 1978; Calluna-Erica cinerea heaths Muir & Fraser 1940, Gimingham 19646, 1972 p.p.; Calluna vulgaris-Sieglingia decumbens Association Birks 1973; Carici binervis-Ericetum cinereae Br.-Bl. & Tx (1950) 1952 emend. Birse 1980 p.p.; Plantago maritima-Erica cinerea Association Birse 1980.

Constant species

Calluna vulgaris, Erica cinerea, Potentilla erecta.

Rare species

Orobanche alba.

Physiognomy

The Calluna vulgaris-Erica cinerea heath is typically dominated by Calluna vulgaris but the cover, height and structure of the sub-shrub canopy vary quite markedly according to the incidence of burning and grazing and the degree of exposure. Where the community is more frequently burned, as where it makes some contribution to grouse-moor in parts of southern Scotland and locally around the east-central Highlands, pioneer and building phases of the heather tend to predominate but, with more sporadic firing, there can be patchworks of even-aged stands through to the mature and degenerate. Very commonly, however, there is also some grazing by stock and deer which helps keep the canopy more closely trimmed and, in extreme cases, exposure to wind and sun can reduce the bushes to a tight and even or windwaved cover but a few centimetres high.

Further modest diversity comes from the frequent but varied contribution of Erica cinerea. This is generally subordinate to the heather in abundance though, being more shade-tolerant, it is well able to persist beneath taller Calluna canopies as a patchy second tier, the rather straggling branches that it often forms in mixed covers becoming semi-prostrate, rooting adventitiously and spreading laterally (Bannister 1965, Gimingham 1972). And, in certain circumstances, it can become locally abundant in this kind of heath, regenerating well after burning, for example, and, especially on southfacing slopes and where there is little grazing (Gimingham 1949), it can rival Calluna in its extent in the middle years of recovery. Vaccinium myrtillus, by contrast, is at most occasional here and only rarely of any abundance and V. vitis-idaea is decidedly scarce. Empetrum nigrum ssp.