Coastal heaths are normally found within 500m from the sea and as a result of salt spray they support coastal species such as spring squill amongst the heather.
Fel arfer, mae rhostiroedd arfordirol i'w cael o fewn 500m i'r môr ac, o ganlyniad i ddistyll y don, maent yn cynnal rhywogaethau arfordirol megis seren y gwanwyn ymhlith y grug.