4.2 (29.79 ha Index 61)
It includes the hills located south of the Departments. of Rocha y Maldonado, occupying an important area around the city of Soca. The relief is strongly undulating with a 4-8% slope with convex interfluves and extended slopes with very few rocky outcrops. A salient characteristic of this unit is the presence of abundant gullies that extend through the concavities of the relief. The dominant soils occupy, within the landscape, the extended slopes and are Typical/Abruptic Subeutric Ochric Argisols, with loamy textures, deep, with moderately good to imperfect drainage and medium to low fertility (Maximum Brown Grasslands). In the strongly convex upper parts, shallower soils and Lithosols develop. The mother material is made up of thin clayey silt sediments that cover the altered crystalline basement. The vegetation is prairie, predominantly winter, with a dense and somewhat open tapestry. The current use is pastoral and partially agricultural. This group corresponds to the San Carlos unit on the chart at a scale of 1:1.000.000 (DSF).
5.02b (19.21 ha Index 88)
It is the most important group, since it occupies more than 80% of the lands in this subzone. It exists repeatedly in the Departments. of Florida and in the Department of Flores (Tips of the San Jose) and in the rest of the region defined for zone 5. The relief is undulating and strongly undulating, with modal slopes of 5 to 7%. The geological material corresponds to variable lithologies of pre-Devonian rocks, such as granites, migmatites, schistose metamorphic rocks (around Rosario), etc. The soils are moderately deep and superficial Subeutric Haplic Brunosols (moderately deep Brown Grasslands and Regosols), to which Inceptisole (Lithosols) are associated, sometimes very superficial. The upper horizon is brown and reddish brown, sometimes yellowish brown, with a loamy texture, gravelly loam or sandy loam with abundant gravel, fertility is medium, sometimes low. The rockiness is moderate and varies between 2 to 10% of the area with outcrops. Throughout the area there may be narrow lowlands, associated with drainage routes of little importance, which contain hydromorphic Luvic Gleysols (Humic Gley) and Typical Eutric or Luvic Brunosols (Black Prairies and Maximal Brown Prairies), which contain very good summer pastures. The use is pastoral. This group corresponds to the San Gabriel-Guaycuru unit on the 1:1.000.000 (DSF) scale chart.
