A small-scale land-classification map is the best guide to the economic geography of Southland. The mountainous country, including the Eyre (summit, 6,650 ft) and the Garvie (summit, 6,086 ft) Mountains, is shown as the southernmost extent of the belt of high-country farming, with outliers appearing in the Takitimu Mountains (summit, 5,559 ft) and the Hokonui Hills. Fringing the uplands is an extensive but interrupted swath of undeveloped and partially developed land with marked concentrations in four areas: along the eastern shores of Lakes Manapouri and To Anau — in fact the upper Waiau valley; on the eastern and southern sides of the Takitimus and west of Nightcaps; around the Hokonui Hills, especially the southern side; and a stretch of coastal country east of Invercargill and extending towards the Catlins.
The central portion of Southland contains the developed land where, in three major lowland districts, the most advanced and intensive farming is practised. Enclosed between the high country and the Hokonui Hills, and drained principally by the Waimea and the upper Oreti and Mataura Rivers, are the Five Rivers and Waimea Plains. Extending west from the Mataura River to the Aparima River is the Southland Plain, its eastern portion being known as the Edendale Plain. East of the Longwood Range lies the plain of the lower Waiau.
The plains are composed of alluvial gravels, the Southland Plain being formed by the coalescing fans of the southward-flowing rivers. Silt loams, clay loams, loess soils, and some recent silts constitute the principal soil types and, in the majority of cases, liming and drainage have proved to be indispensable to their productive development. This is in part a response to the leaching caused by high rainfall and to the original deficiencies of the podzolised yellow-brown earths and especially of the moderately acid yellow-grey earths of the Five Rivers and Waimea districts; whilst the low gradient of the plains and the resultant subsoil clay pan formation explains the need for drainage. The climate is responsible for the other principal feature of Southland farming, the provision of adequate winter feed, and the distribution of the rainfall within the region underlies some of the contrasts in the farming systems.