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Mid Altitude Environments
At mid altitudes, the uplands and hillslopes that occur extensively in inland areas of the South Island, are characterised by cool soil temperatures (<6 C) and moist soil conditions (though drier than high altitude areas), resulting in reasonable plant growth rates. The yellow brown earth 
are naturally of low fertility, as the nutrients have been removed by leaching.
The predominance of native species in mid altitude tussock grassland communities depends on the area's management history, pest population levels, climate, and on-going management.
Why tussock grasslands are here
Prehuman HistoryIn pre-human times, tussock grasslands would never have been the climax vegetation type at this altitude, except in localised areas which were too dry, wet or frosty for woody vegetation to grow. However, the occurrence of natural fires would have removed patches of the climax forest cover. These areas would have slowly been recolonised, firstly by short tussock species, followed by tall tussock species which naturally occupied the high altitude areas above the upper tree limit. Therefore, at any one time, some part of the montane environment would have been occupied by tall or short tussock grasslands, which would later be out competed by tall trees or shrub species. More recent pastoral management
Although not always cost effective to develop and maintain the increased production achieved by aerially oversowing and top dressing tussock grasslands in this zone, many mid altitude tussock grasslands have some exotic plant component, and are usually more modified than those at high altitude. The snow tussock canopy is usually opened up to maintain stock access, provide a niche for the more palatable intertussock species to grow, while woody plants require removal to maintain the above. Management tools to maintain an open tussock cover include burning and grazing. Such disturbance makes tall tussock grasslands more prone to invasion by exotic species, which are better adapted to a disturbed environment. Conservation management today
Today's management of tussock grasslands in this altitudinal zone therefore needs to recognise that while tussock grasslands may have been present here in the past, is isn't the natural climax vegetation type. Burning and/or grazing may be required to maintain these grasslands as grasslands where woody plants regenerating from existing patches, or germinating from the seed bank, are likely to become dominant. Woody communities may have exotic species present, e.g. wilding pines. The presence of such weeds may well dictate which management goal is feasible. i.e. where the spraying or mechanical removal of wilding pines is not possible, control by burning is also likely to prevent native woody plant regeneration, so the management goal, by default becomes one in which the grassland is maintained as a grassland. Reference:
Connor, H.E. 1964: Tussock grassland communities in the middle Rakaia valley, Canterbury, New Zealand. NZ J Botany 3: 261-276.
Floate, M.J.S. Ed. 1992:Guide to tussock grassland farming. Chapters 2 & 3 AgResearch, Mosgiel, Invermay.
Molloy, B.P.J.; Burrows, C.J.; Cox, J.E.; Johnston, J.A.; Wardle, P. 1963: Distribution of subfossil forest remains, eastern South Island, New Zealand. New Zealand journal of Botany 1:68-77.Wardle, P. 1991: Vegetation of New Zealand. Cambridge Press.