In places head deposits have accumulated and thin podzolic soils have formed over the granite which is ideal for the formation of waved maritime heath vegetation.
[2] Western gorse (Ulex gallii), heather (Calluna vulgaris) and bell heather (Erica cinerea) are the main components of the waved maritime heath and on the deeper soils bracken (Pteridium aquilinum), European gorse (U. europaeus), bramble (Rubus fruticosus) and honeysuckle (Lonicera periclymenum) are encroaching and devaluing the vegetation which is why the condition of the SSSI is considered to be unfavourable recovering.
[5] Two unusual plants (for the Isles of Scilly) in the species–rich maritime grassland are spring squill (Scilla verna) and thyme (Thymus polytrichus).
[4] The dominant species are red fescue (Festuca rubra), Yorkshire fog (Holcus lanatus), thrift (Armeria maritima), sea beet (Beta vulgaris subsp.
They include the common sea ivory (Ramalina siliquosa), the nationally scarce Roccella fuciformis, R. phycopsis, and golden hair-lichen (Teloschistes flavicans); and the BAP species ciliate strap-lichen (Heterodermia leucomela).