Grass is defined as monocotyledonous, herbaceous plants with inconspicuous flowers and long, narrow leaves. On the one hand, a grass is a single such plant or a nonspecific category for the biological classification of such plants. On the other hand, grass is the planted plant cover on the ground (as a meadow or lawn) or the entirety of grassy plants which are eaten by animals or harvested by the farmer during mowing (see also Grünland).
Grass is the livelihood of many animals, especially ruminants and solipeds. A closed plant cover on the ground greatly reduces the area (denudation), the soil is less removed, humus is formed.
Botanically, grasses belong to the order of the sweet-grassy species; The two main groups are sweet grasses and sour grasses. Grasses appeared for the first time in the Cretaceous period, whereupon the erosion behavior of the affected continent greatly changed.