Yes, it is really interesting to see all types of soils and discover their characteristics and major elements. By sight, it is very likely that the red earth is due to soils rich in iron, meaning that iron is mainly responsible for the red earth. This is found in the form of iron oxides, such as hematite. Iron plays an important role in the availability of nutrients to plants. The red color is also due to another element that is less available but plays its role, for example aluminum found in minerals such as kaolinite. It can affect soil acidity and water holding capacity. This is important because depending on the pH of the soil, aluminum can influence the soil favorably or negatively. Since the pH of a soil is very important because at a very acidic pH, for example, the soil does not absorb certain elements and therefore becomes infertile soil. Also another chemical element that must be found is silicon, which is an important component in many clay minerals present in red soils. Of course, there must also be other elements such as Manganese; Zinc, magnesium and others. You know, I would like to analyze that soil and verify if it is suitable for cultivation and if not, amend it with certain nutrients and friendly agrochemical techniques to improve the soil. It is very important to determine the organic matter of the soil, as well as the pH, which I already mentioned, as well as the conductivity and availability of Nitrogen, which also influences the quality of the soil. Anyway, if you bring me at least 10Kg of soil, I can do a good analysis of your soil @solominer jj
RE: Moving on to the second retaining wall