Magellanic Steppe Zone

This zone can be further subdivided into grassland, scrub and heathland. The grassland plains are dominated by Festuca gracillima together with endemic grasses such as Agrypyron fuegianum (Poaceae) in the dryer areas and Alopecurus magellanicus, Deschampsia antarctica and D. kingii in the wetter areas. Among the frequent associates are various endemic or near endemic herbs such as Draba magellanica (Brassicaceae), Senecio magellanicus (Asteraceae), Silene magellanica (Caryophyllaceae) and Sisyrinchium patagonicum (Iridaceae), while endemics or near endemics such as Anagalis alternifolia (Primulaceae), Gentianella magellanica (Gentianaceae) and Gunnera magellanica (Gunneraceae) occupy the wetter grasslands. The area also includes saline grasslands dominated by the endemic or near endemic Puccinella biflora and P. magellanica (Poaceae) together with other endemics or near endemics like Chenopodium antarcticum (Chenopodiaceae), Colobanthus quitensis (Caryophyllaceae), Eriachaenium magellanicum (Asteraceae), Plantago barbatum (Plantaginaceae) and Suaeda argentinensis (Chenopodiaceae). Dominant scrub species are Lepidophyllum cupressiforme, Chiliotrichum diffusum and to a lesser extent Pernettya mucronata. The former is characteristic of coastal and some inland dune systems where it is often associated with shrubs such as Berberis buxifolia and Senecio patagonicus. The lower layers include endemics such as Berberis empetrifolia (Berberidaceae), Boopis australis (Calyceraceae), Descurainia antarctica (Brassicaceae) and Jaborosa magellanica (Solanaceae).  Throughout the steppe of northern Isla Grande and within some of the Nothofagus forests, the more acidic areas support heathland dominated by the ericoid dwarf shrub Empetrum rubrum. Among the associates are endemic or near endemic species such as Arjona patagonica (Santalaceae), Azorella lycopodioides (Araliaceae), Baccharis magellanica (Asteraceae), Festuca magellanica (Poaceae), Lycopodium magellanicum (Lycopodiaceae), Nassauvia darwinii (Asteraceae) and Nanodea muscosa (Santalaceae). However, in some of the coastal gravel areas the endemic Nardophyllum bryoides (Asteraceae) assumes local dominance to form a type of non-ericoid heath.

Magellanic Deciduous Woodland Zone

South of the steppe zone, deciduous forest extends from sea level to an altitude of about 500 m in sheltered areas. Nothofagus pumilio is the dominant tree at low elevations where there are well developed soils with good drainage, but in the less favourable areas where soil is more acidic or where there is a high water table, Nothofagus antarctica become the more dominant species. In some of the more well developed Nothofagus pumilio forests the canopy becomes so dense that shrub and herb layers are virtually absent, but where there is more light penetration species may include Adenocaulon chilense, Codonorchis lessonii and endemics or near endemics such as Macrachaenium gracile (Asteraceae), Misodendron punctulatum and M. quadriflorum (Misodendraceae).  The canopy in Nothofagus antarctica forests, on the other hand, is usually more open allowing rich shrub and herb layers to develop. Common amongst these are Berberis buxifolia, Embothrium coccineum, Osmorhiza chilensis, Uncinia lechlerian, and the endemic Vicia magellanica (Fabaceae). Open areas of both deciduous and evergreen forests are the characteristic locations of Chiliotrichus diffusum - Berberis buxifolia scrub where endemics such as Acaena ovalifolia (Rosaceae), Baccharis patagonica (Asteraceae), Calceolaria biflora (Calceolariaceae), Maytenus magellanica (Celastraceae) and Ribes magellanica (Grassulariaceae) can be found. Pernettya scrub occurs in some of the wetter areas where it may include the endemic Berberis ilicifolia (Berberidaceae). In some of the flatter areas where the water table approaches the surface, there are mesophytic grasslands, which are similar to steppe grasslands, but species such the endemic Carex magellanica (Cyperaceae)and Geum magellanicum (Rosaceae) give these grasslands a distinctive appearance. Where the water table reaches the surface, local bogs may form replacing the deciduous forest. These can be divided into Sphagnum bogs and Marsippospermum bogs. In the former Sphagnum magellanicum is usually the dominant species, but may be accompanied by endemics such as Astelia pumila (Asteliaceae), Carex magellanica (Cyperaceae), Gunnera magellanica (Gunneraceae), Pinguicula antarctica (Lentibulariaceae) and Tetronicum magellanicum (Juncaginaceae). In areas where the climate is slightly dryer Marsippospermum grandiflorum becomes the main species while frequent associates include endemics or near endemics such as Rostkovia magellanica (Juncaceae) and Schoenus antarcticus (Cyperaceae).

Magellanic Evergreen Forest

Towards the south and west of Fuegia the deciduous trees give way to evergreen forests. These can be roughly divided into Nothofagus betuloides forest and Pilgerodendron uvifera forest. The best stands of Nothofagus betuloides forest occur away from the coast on well-drained, peaty soil. The endemic Philesia magellanica (Philesiaceae) is locally sub-dominant, but in general the commonest associates include Lebetanthus myrsinites and the endemic Berberis ilicifolia (Berberidaceae) and Blechnum magellanicum (Blechnaceae) in the scrub layer, and Luzuriaga marginata (Smilacaceae), Senecio acanthifolius (Asteraceae) and various filmy ferns such as Hymenophyllum pectinatum, H. secundum and H. tortuosum (Hymenophyllaceae) in the herb layer. In coastal areas, the primitive flowering plant Drimys winteri becomes co-dominant with Nothofagus betuloides, while the shrub layer often incudes the attractive Desfontainia spinosa. Prior to human intervention, it is thought that there were also forests co-dominated by Drimys winteri and the endemic Maytenus magellanica (Celastraceae). The Pilgerodendron uvifera forests only occur in the very wet areas and typically have a ground flora dominated by Sphagnum moss, but may also include endemics such as Acaena pumila (Rosaceae) and Perezia magellanica (Asteraceae). Also in coastal areas the evergreenforests are usually fringed by scrub dominated by the endemic Fuchsia magellanica (Onagraceae), but both Ribes magellanicum and Pernettya mucronata may be locally dominant or co-dominant in these situations, while in some of the more exposed areas Hebe elliptica may form the main species. Grasslands can also be found here in the openings between woodland and scrub. Prominent species in these areas include the endemic Poa alopecurus subsp. faegiana and Deschampsia kingii (Poaceae).  The bogs in this zone are characterised by Sphagnum moss, but also typically include Oreobulus obtusangulus, Schoenus andinus, Senecio trifurcata and the endemic Donatia fascicularis (Donatiaceae).

Magellanic Moorland

In the high rainfall areas in the western and southern parts of Tierra del Fuego there are a series of bog communities collectively known as Magellanic Moorland. Extensive areas of blanket peat characterize the zone, but the bogs can be broadly divided into two major types - cushion bog and graminoid bog. The former, as expected, comprises a dense, low covering of cushion plants such as Bolax caespitosa, Drapetes muscosus, Gaimordia australis together with endemics such as Caltha dioneifolia (Ranunculaceae) and Phyllachne uliginosa (Stylidaceae). Graminoid Bogs are principally composed of grass-like plants such as Schoenus antarcticus and the endemic Tetroncum magellanicum (Juncaginaceae). Some of the most consistently encountered associates of both these bogland types are Drosera uniflora, Gaultheria antarctica and the endemic Gunnera lobata (Gunneraceae) and Nanodea muscosa (Santalaceae).

Magellanic Alpine Zone

Above an altitude of about 600 m on Isla Grande the forests give way to alpine vegetation, and just above the timberline, this is mainly composed of cushion heath where Bolax gummifera forms the dominant cushion forming species. Between the cushions, species such as Gamochaeta spiciformis and Stipa rariflora occur, while the endemic or near endemic Saxifragodes albowiana (Saxigragaceae) and Tetrachondra patagonia (Tetrachondraceae) are virtually confined to these communities. With increasing altitude, the heath becomes more open providing habitat for Azorella selago and endemics such as Onuris alismatifolia (Brassicaceae), Saxifragella bicuspidate (Saxifragaceae), Viola tridentate (Violaceae) and in some of the more unstable areas Nassauvia pigmaea (Asteraceae). Intergrading with cushion heath are areas dominated by dwarf shrub heath in which Empetrum rubrum is usually the dominant species. Here additional endemics such as Grammitis magellanica (Polypodiaceae), Hymenophyllum falklandicum (Hymenophyllaceae) and Senecio darwinii (Asteraceae) can be found. At even higher altitudes, many of the Fuegian Mountains have extensive areas of gently sloping terrain covered by talus deposits. Much of this is devoid of vegetation, but there are occasional patches of feldmark often composed of species such as Moschopsis rosulata together with endemics like Nassauvia lagascae, N. latissima (Asteraceae) and Senecio humifusus (Asteraceae). In the Fuegian highlands south of the Azopardo-Fagnano Depression, there are frequent glacial seepage areas which carry distinctive vegetation sometimes inappropriately described as alpine meadow. Along the stream margins are mats of Caltha appendiculata and the endemic Abrotanella linearifolia (Asteraceae) amongst which grow other endemics such as Ourisia fuegiana (Plantaginaceae), Primula magellanica (Primulaceae) and Tapeinia obscura (Iridaceae), but where the substrate becomes more rocky or composed of coarser soil Cardamine glacialis and the endemic Hamadryas magellanica (Ranunculaceae) and Nassauvia magellanica (Asteraceae) become the major species. Prominent species in the more marshy areas include the endemic or near endemic Agrostis magellanica (Poaceae) and Rostkovia magellanica (Juncaceae).

Magellanic Maritime Tussock Grass

One of the most conspicuous coastal vegetation types on some of the islands is a giant tussock grass community dominated by Poa flabellata with some tussocks growing up to 3 m high.  In some of the more open areas, associated species include Alopecurus antarcticus and Poa antarctica and on the Falkland Islands the Falkland endemic Senecio littoralis (Asteraceae).

Magellanic (Falkland Island) Vegetation

Most of the Falkland Islands are covered with either Cortaderia pilosa tussucks or Empetrum rubrum heath. The former has tussocks growing up the 40 cm high, but these are usually spaced out sufficiently to allow a number of associates to co-exist such as the Falkland endemics Chevreulia lycopodioides (Asteraceae) and Leucheria suaveolens (Asteraceae). The Empetrum heath is best developed in the comparatively dry areas, especially on the island’s many rocky ridges. Falkland endemics found here include Erigeron incertus (Asteraceae), Gnaphalium affine (Asteraceae) and Calandrinia feltonii (Portulacaceae) although the latter species may now be extinct. In the coastal areas, the heath also provides refuge for the Falkland endemics Arabis macloviana (Brassicaceae) and Nassauvia gaudichaudii (Asteraceae). In some of the more rocky areas the fern Blechnum magellanica can become co-dominant with Empetrum and in these areas the Falkland endemic Senecio vaginatus (Asteraceae) can be found. Above altitudes of about 600 m the islands support a felmark community in which species of Azorella, Bolax gummifera, Colobanthus subulatus and Abrotanella emarginata predominate. These areas also include the Falkland endemic cushion forming species Valeriana sedifolia (Valerianaceae), but feldmark with Valeriana sedifolia also occurs on some of the exposed coastal cliff tops where other Falkland endemics such as Hamadryas argentea (Ranunculaceae) and Nastanthus falklandicus (Calyceraceae) can be found. Bush formations on the Falklands are quite rare and usually dominated by either Chiliotrichum diffusum or Hebe elliptica in the coastal zones. The former provides habitat for the Falkland endemic Nassauvia serpensi (Asteraceae). The islands freshwater formations can be divided into Eleocharis melanostachys associations and Myriophyllum elatinoides associations, and an important component of both communities is the Falkland endemic Lilaeopsis macloviana (Apiaceae).

Other species endemic or near endemic to the Magellanian BioProvince include Abrotanella submarginata, Acaena lucida, Adesmia lotoides, Agropyron elymoides, Agropyron magellanicum, Androsace pusillus, Atriplex reichei, Boopis patagonica, Carex fuscula, Carex vallis-pulchrae, Chiliophyllum fuegianum, Daucus montanus, Draba australis, Eleocharis albibracteata, Ephedra frustillata, Epilobium conjungens, Festuca cirrosa, Frankenia chubutensis, Gunnera lobata, Gutierrezia baccharoides, Hamadryas delfinii,  Hypochoeris patagonica, Juncus chilensis, Juncus stipulatus, Nassauvia fuegiana, Perezia pilifera, Perezia lactucoides, Poa darwinii, Poa yaganica, Ranunculus pseudotrullifolius, Rumex magellanicus, Saxifraga magellanica, Senecio arnottii, Senecio eightsii and Senecio websteri.

Magellanic Saltmarsh

In the steppe region of Tierra del Fuego (part of the Magellanic steppe) coastal saline zones could be divided in to salt shrublands, saltmarsh and salt carpet. 

Salt Shublands
Characterised by shrub Lepidophyllum cupressiformis these stands occurred on relatively dry soils and sand deposits in both estuarine and lacustrine zones. Other typical species included Azorella filamentosa, Azorella monantha, Azorella trifurcata, Armeria maritima, Carex macrosolen, Colobanthus subulatus, Deschampsia patula, Festuca gracillima, Hordeum lechleri, Hordeum pubiflorum, Lepidium pseudo-didymus, Phleum alpinum, Plantago maritima, Poa pratensis, Poa spiciformis, Taraxacum officinale, Trisetum spicatum, and the endemic or near endemic Acaena magellanica, Alopecurus magellanicus, Azorella fueguiana, Puccinellia magellanica and Puccinellia pusilla.

Saltmarsh
These grass dominated saltmarsh are characterised by Hordeam lechleri and species of Pucciniellia including the endemic Puccinellia magellanica and Puccinellia pusilla. They are mainly located where water discharges into playas in the Tertiary zones or adjacent to small lakes and swales on the upper tidal plains. Associated species include Armeria maritima, Azorella filamentosa, Azorella monantha, Colobanthus subulatus, Deschampsia antarctica, Deschampsia patula, Hordeum lechleri, Hordeum pubiforum, Juncus scheuchzerioides, Lepidophyllum cupressiforme, Lepidium pseudo-didymus, Plantago maritima, Poa atropidiformis, Poa spiciformis, Rumex crispissimus, Sarcocarnia perennis, Taraxacum officinale, Trisetum spicatum and the endemic or near endemic Carex vallis-pulchrae, Eriachaenium magellanicum, Puccinellia magellanica and Puccinellia pusilla.

Salt Carpet
This is described as a prostrate community dominated by the succulent halophyte Sarcocornia perennis and characteristically found on low intertidal salt flats. Associated species include Armeria maritima, Hordeum lechleri, Hordeum pubiforum, Poa atropidiformis, Puccinellia biflora, Sedum acre and the endemic or near endemic Puccinellia magellanica and Puccinellia pusilla.

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