They are characterized by the presence of undergrowth (grasses) and small shrubs, distant from each other.
This type of vegetation is found in two distinct places. The terra firme fields (low grass savannas) are characteristic of northern Amazonia, Roraima, Pará and Bananal and Marajó islands, while the clear fields (wet steppes) are typical of the southern region, giving rise to the famous "Pampas Gaúchos" "
The clear field is devoid of trees, very uniform and with scattered and scattered bushes. In the fields of dry land, the trees, low and spaced, are totally integrated into the landscape. In both cases the soil is covered with grasses, shrubs and herbs.
Between Rio Grande do Sul and Santa Catarina, native grass and legume fields stretch like a green carpet over 200,000 km², becoming denser and richer on the slopes. In this region, with much intertwined forest, rainfall is regularly distributed throughout the year and low temperatures reduce evaporation levels. Such weather conditions end up favoring tree growth. This does not occur in fields in northern areas of the country.
Due to the richness of the soil, southern cultivated areas expanded rapidly without an adequate tillage system, resulting in erosion and other progressively worsening problems. Fields are widely used for rice, corn, wheat and soy production, sometimes in association with cattle raising. Inattention to the soil, however, leads to desertification, recorded in different areas of Rio Grande do Sul.
Cattle and sheep farming is also part of the local culture. However, repeating the same mistake as farmers, the shepherd is causing soil degradation. In the dry season, when pastures dry up, the same number of animals continue to dispute smaller areas. With the grass almost bare, the pressure on the soil that opens in veins grows.
When the rains start again, the waters flow through these depressions and start the erosion process. The fire used to eliminate dry pasture remains makes the soil even more fragile.