[4] The Isles are not so exposed to gales as the Western Rocks; consequently the soils do not receive so much salt spray, and remnant habitats such as coastal grassland and maritime heath have survived the inundation of the sea.

[5] The Isles of Scilly are a Geological Conservation Review (GCR) site for the largest assemblage of tied islands outside of Orkney and Shetland.

[6] Most of the islands have dense cover of bramble Rubus fruticosus and bracken Pteridium aquilinum and grassland along the coastal fringes.

Goldenrod (Solidago virgaurea) is locally abundant amongst the heath communities growing on the podzolic soils on the higher parts of the islands.

Four other mammals have been recorded: rabbit, brown rat described as a plague on some of the Eastern Isles,[10] house mouse and the so-called Scilly shrew.

'great saltwater downs') (grid reference SV947145), is the largest of the Eastern Isles and consists of two hills joined by a low sandy neck.

The area of blown sand is dominated by marram grass (Ammophila arenaria) which helps to stabilise the dunes and shelter a relatively rich flora of non-maritime plants such as a stunted grey sallow (Salix cinerea).

[11] The island as a few patches of heather and some strandline vegetation on the sheltered parts of its shore, while Little Arthur has bracken on the deeper soils and heath on the summit with English stonecrop in the bare areas.

Also on Little Arthur is a small area of strandline vegetation and sand dunes with slender St John's-wort (Hypericum pulchrum); a plant common in Cornwall but uncommon in the Isles of Scilly.

Other species recorded include Yorkshire fog, orache, common scurvy-grass and tree-mallow which forms temporary stands in some years.

Bracken dominates the slopes and there are maritime grassland and cliff communities along the coast which has several small caves on the east side.

Great Innisvouls (Cornish: Enys Vols Meur, great wether island) (grid reference SV953141), has a small area of maritime grassland and bracken, and Little Innisvouls (Cornish: Enys Vols Bian, little wether island) (grid reference SV955142) has strandline plant species.

[5] Nornour (Cornish: Ar Nor, facing the mainland) (grid reference SV944148), consists of one hill covered in bracken to the north of Great Ganilly, joined to it at low tide by a boulder causeway.

[5] There was a long period of habitation during the Bronze and Iron Ages when Nornour would have been part of a larger island; after a storm in 1962, the erosion of sand dunes uncovered hut circles.

Analysis of the brooches indicate they came from numerous places in Britain and the Continent; given that there are no comparable sites on Scilly, this suggests that the finds were not for trade but perhaps for paying respect to a local cult.

She hit Irishman's Ledge (grid reference SV947149) on 16 July 1872, when the Captain attempted to take a short cut through English Island Neck.

[9] Ragged Island (grid reference SV946138) has two unexpected plants; Chilean hard-fern (Blechnum cordatum) and borage (Borago officinalis).

[8] Guther's (or Gunther's) (Cornish: An Gudhys) (grid reference SV918144), is a small island which lies on the western side of the Eastern Isles and south of St Martin's.

[5] It is possible to walk out to this island from St Martin's at exceptional low tides, but great care must be taken not to be cut off.

Hanjague (Cornish: Henjek) (grid reference SV957150) is a sea stack approximately one km north-east of Great Gannilly, and is the easternmost island in the archipelago.