At first only such plants were grown as would serve for human food; natural meadows and pastures provided for domestic animals. Even now there are large areas where no special efforts are made to secure food for stock. With increasing population, however, more ground must be devoted to cereals for human food, and the value of land rises. Natural pastures largely disappear and the farmer must grow other crops as food for stock during different seasons. The cultivation of fodder and pasture plants has reached its greatest perfection in temperate regions, where the animals cannot graze during the winter.