2.21 (7.76 ha Index 105)
The relief is hilly, with convex interfluves and slopes between 6 and 12%. The soils are Luvic Brunosols (maximal Brown Grasslands), loams and Abruptic Melanic Subeutric Argisols, sometimes moderately deep loams (Planosolic Grasslands). Brunosols occur on convex or flat slopes, while Argisols are related to the softer upper zone of the interfluves. This soil pattern occurs in the south of the Department of Treinta y Tres and north of Rocha, while in the south of Rocha y Maldonado Brunosols with finer textures and greater natural fertility dominate. Associated with these, thinner soils occur: moderately deep rhodic Luvic Brunosols (Red Prairies) and occasionally Melanic Subeutric Lithosols, sometimes very superficial. Both are related to more dissected areas or eruptions, or to proximity to rocky outcrops. The mother material is made up of a weak mantle (sometimes discontinuous) of Quaternary clayey silt sediments on the crystalline basement rock. The vegetation is predominantly summer grassland, and the current use is pastoral. It occupies important areas to the west and southwest of Treinta y Tres, surroundings of Velazquez and south of the Department of Maldonado. The soils in this group correspond to the Jose Pedro Varela unit of the chart at a scale of 1:1.000.000 (DSF).
2.10 (2.80 ha Index 9)
It corresponds to very rocky mountain ranges and flattened rocky mountain ranges, with a general SW-NE orientation. The flattened rocky mountain ranges constitute the highest parts of the group, and their surface has a high density of outcrops (more than 40%), while the very rocky mountain range rocky constitutes high interfluves, strongly undulated with abundant outcrops. The underlying rocks are generally intrusive granites; quartzite components of the group Lavalleja and acid effusive rocks. The soils are District Umbrian (sometimes Subeutric) or Melanic Lithosols, gravelly and usually very superficial, with sandy or gravelly sandy textures, with moderately deep Typical Subeutric Brunosols as accessory soils. The rockiness is very high and more than 40% of the surface It is covered in outcrops. The current use is pastoral. There are important areas of this group in the Sierra de Carape and the Sierra de la Coronilla, to the E. and SE. of Aigua, Sierra de Animas, and isolated hills such as Marmaraja, Arequita, etc. This The group includes the soils of the Carape and Sierra de Animas units, and some of the Sierra de Aigua unit on the chart at a scale of 1:1.000.000 (DSF).
2.11b (1.23 ha Index 26)
They are rocky mountain ranges with a strongly undulating landscape and slopes greater than 20%. In the first case, it exists in discontinuous patches, correlated with intrusive granites, where the percentage of rockiness reaches between 10 and 40% of the area with exposed rock. The dominant soils are Subeutric Melanic Lithosols, gravelly sandy, sometimes stony and very superficial; with rocky outcrops and Haplic Subeutric Brunosols, sandy gravelly loam and gravelly loam, superficial, stony (Regosols). They may present mountainous mountains. In the second case, the landscape is broken with slopes greater than 15% that can reach values of 30 to 40%, being characteristic of the hills belonging to the Sierra de Aigua and the broken landscapes existing south of the city of Minas, observable by Route 60. Mostly this situation is correlated to lithologies corresponding to the group Lavalleja and undifferentiated metamorphic rocks. In general, in the association of soils, the superficial ones predominate (District Subeutric Lithosols), existing in the concavities and gorges, deep soils, of colluvial origin that normally contain high-density mountain forest. The use is pastoral and the vegetation is grassland with a predominance of summer species, with associated weeds (Baccharis trimera, etc.). This group integrates the Santa Clara and Sierra de Aigua units of the chart at a scale of 1:1.000.000 (DSF).
03.41 (0.22 ha Index 158)
This group corresponds to the large plain that is located on both banks of the Santa Lucia River, mainly in the section in which it is bordering between the Departments. of Canelones y Florida. A reference place is the Pueblo San Ramon, since to the north of it it appears with a significant extension. It is a high plain, occasionally flooded, with mesorelief, where high positions are dominant and present Melanic Eutric Planosols and Luvic Eutric Brunosols, hydromorphic (Brown to Maximum Black Grasslands) developed on clayey silt sediment, with very dark brown upper horizons. black, silty loam texture, high fertility and imperfect drainage. In high positions there may also be Eutric Argisols, sometimes Subeutric, Typical Melanic (Maximal Brown Grasslands). In depressed positions the Planosols already mentioned occur, although with a horizon of variable thickness (10 to 40 cm.), of accumulation (cumulic), of very dark gray to black color and texture of silty clay loam to silty clay. Also in depressed and humid positions there are Melanic Luvic Gleysols (Humic Gley), and associated with the water course in areas of alluvial sediments, Melanic Heterotextural Fluvisols (Alluvial Soils) develop, with river jungle vegetation. The use is pastoral, with high quality summer and winter pastures and parks of variable density, with the only limitation being the risk of flooding. This group corresponds to the San Ramon unit on the 1:1.000.000 (DSF) scale chart.
