Answer:
The steppe crosses the Russian plain, south of the taiga, penetrating deep into Siberia. It comprises three main types, which run in roughly parallel bands from east to west: forest steppe in the north, through steppe, to semi -desert steppe in the south. Within these belts, zones of temporary inundation on floodplains or in zones of internal drainage provide valuable hay land. The steppe was increasingly ploughed for crops during the twentieth century; initially crops were rotated with naturally regenerated grassland, but from mid-century cultivation was increasingly intensive. During the collective period, the emphasis was on industrial stock rearing, with housed cattle and high inputs; since decollectivization, intensive enterprises are closing for economic reasons, and systems have yet to stabilize. If ploughed land is left undisturbed it will return naturally to steppe vegetation in six to fifteen years. Hay is very important for winter feed, and much is made from seasonally flooded meadows. Many marginal, semi-arid areas of the steppe have been put under crops, but are not economically viable; much of the cereals so produced are fed to livestock, but grain yields are very low and yield no more livestock products than would natural grassland, but at far higher cost. Marginal cropland should return to grass.