Included here is the Juan Fernandez Islands, which mainly comprises Alejandro Selkirk (Masafuera), Robin Crusoe (Masatierra), Santa Clara and the Desventuradas Islands (San Ambrosio and San Felix). Several upland ecosystems have been described.

Fernandezian Upland Grassland

The natural grasslands of both Masafuera and Masatierra are dominated by Stipa laevissima and S. neesiana. Their yellow appearance in summer gives them the look of dry steppe. On Masafuera they occur on the eastern slopes and on the high west barranca. The few other associated species of native origin include Halorrhagis masafuerana (Halorrhagidaceae), Nicotiana cordifolia (Solanaceae) and Wahlenbergia masafuerae (Campanulaceae) all of which are endemic to Masafuera. The remnants of native grassland on Masatierra occur on the northern slopes of the island. Here the associated species include the rare endemic Wahlenbergia fernandeziana (Campanulaceae), while in the more stony areas shrubs such as the endemic Rea pruinata (Asteraceae) make an appearance. Bryophytes, such as Ptychomnium fernandezianum and Rhacopilum fernandezianum, and lichens are also important elements especially in the more rocky areas.

Fernandezian Upland Brushwood

Brushwood or scrub appears to form the climatic climax vegetation on exposed ridges such as on the crest of Cordon Escarpado and at the foot of steep escarpments. Virtually all the dominant shrubs are endemic. On Masatierra these include Berberis corymbosa (Berberidaceae), Colletia spartioides (Rhamnoides), Cuminia fernandezia (Lamiaceae), Dendroseris marginata, Robinsonia gayana (Asteraceae), Eryngium bupleuroides (Apiaceae), Escallonia callcottiae (Saxifragaceae), Pernettya rigida (Ericaceae), and Selkirkia berteroi (Boraginaceae). However, the composition of species dominating the shrub layer varies from place to place. In the more exposed areas Escallonia callcottiae and Pernettya rigida are usually the main species. Another frequent plant of shrub stature is the large endemic herbaceous species Gunnera bracteata (Gunneraceae). The field layer is likewise populated mainly by endemic species such as Erigeron fruticosus (Asteraceae), Halorrhagis masatierrana (Halorrhagidaceae), Margyricarpus digynus (Rosaceae), Plantago fernandezia (Plantaginaceae) and Wahlenbergia fernandeziana (Campanulaceae). At ground level bryophytes, such as Lepidozia fernandeziensis and Ptychomitrium fernandezianum, and lichens, like Blastenia fernandeziana and Porina fernandeziana, usually predominate. 

Fernandezian Subalpine Fern-Grass Heath

Confined to the higher island of Masafuera these heathlands make their appearance at an altitude of about 700 m. They are typically dominated by Lophosoria quadripinnata, the endemic tree fern Dickinsonia externa (Dickinsoniaceae) and the endemic Gunnera masafuerae (Gunneraceae). Other less common shrubs include the endemic Robinsonia masafuerae (Asteraceae), while the field layer commonly includes Pernettya rigida and the endemic eyebright Euphrasia formosissima (Scrophulariaceae).

Fernandezian Alpine Fern-Grass Heath

At an altitude of about 1100 m on Masafuera, the heath becomes more alpine in character and most of the shrubs take on a stunted appearance. At these altitudes there is a significant Magellanian element represented in part by Lagenophora hariotii, Rubus geoides, Uncinia brevicaulis and the endemic Acaena masafuerana (Rosaceae), Galium masafueranum (Rubiaceae) and Luzula masufuerana (Juncaceae). The dominant grasses include the two endemic species Agrostis masafuerana and Bromus masafuerana (Poaceae), while the main fern is Gleichenia quadripartita.  Other endemic species characteristic of this zone includes Abrotanella crassipes, Erigeron luteoviridus (Asteraceae) and Urtica masafuerae (Urticaceae). Several of these alpine heath species, particularly Abrotanella crassipes, can be found on the summit ridge of Los Inocentes at 1500 m. Bryophytes and lichens are also well represented including Thuidium masafuerae and Caloplaca selkirkia.

References

Crawford, D. J., Sang, T.,  Stuessy, T. F., Kim, S. & Silvao, M 1998. Dendroseris (Asteraceae: Lactuceae) and Robinsonia (Asteraceae: Senecioneae) on the Juan Fernandez Islands: similarities and differences in biology and phylogeny.  In: Evolution and Speciation of Island Plants. Eds. T. S. Stuessy and M. Ono. Cambridge University Press.

Dirnbock, T., Greimler, J., Lopez, P. & Stuessy, T. F. 2003. Predicting future threats to the native vegetation of Robinson Crusoe Island, Juan Fernandez Archipelago, Chile. Conservation Biology, 17: 1650-1659.

Mueller-Dombois, D. & Fosberg, F. R. 1998. Vegetation of the Tropical Pacific Islands. Springer.

Skottsberg, C. 1920-1953. The natural history of Juan Fernandez and Easter Island. Volume II. Botany. Almqvist and Wiksells Bokteyckeri, Upsala.

Stuessy, T. F., Crawford, D. J. Marticorena, C. & Rodriguez, R. 1998. Island biogeography of angiosperms of the Juan Fernandez archipelago.  In: Evolution and Speciation of Island Plants. Eds. T. S. Stuessy and M. Ono. Cambridge University Press.

Stuessy, T. F., Crawford, D. J. Marticorena, C. & Silvao, M 1998. Isolating mechanisms and modes of speciation in endemic angiosperms of the Juan Fernandez Islands.  In: Evolution and Speciation of Island Plants. Eds. T. S. Stuessy and M. Ono. Cambridge University Press.

Stuessy, T. F., Marticorena, C., Rodriguez, R. R., Crawford, D. J. & Silva, M. O. 1998. Endemism in the vascular flora of the Juan Fernandez Islands. Aliso, 13: 297-307.

Stuessy, T. F., Sanders, R. W. & Silva, M. 1984. Phytogeography and evolution of the flora of the Juan Fernandez Islands. In: Biogeography of the Tropical Pacific (Proceedings of a Symposium). Eds. F. J. Radovsky, P. H. Raven and H. Sohmer. Bishop Museum Special Publication No. 72.

Stuessy, T. F., Swenson, U., Crawford, D. J., Anderson, G. & Silva, M. O. 1998. Plant conservation in the Juan Fernandez Archipelago, Chile. Aliso, 16: 89-101.