1. Judgment of acidic and alkaline soils by soil sources



The soil in mountain forest, gully humus soil, generally black or brown soil, is loose, fertile, good permeability, is a very good acid humus soil. For example: pine needle humus soil, peat humus soil and so on.





2. Judgment of acidic and alkaline soils by surface plants



When collecting soil samples, we can observe the plants growing on the surface. The soil of pine, fir and azalea is mostly acid soil, while the soil of millet, sorghum and halogen is mostly alkaline soil.





3. Judgment of acidic and alkaline soils by soil color



Acidic soils are generally darker in color, mostly dark brown, while alkaline soils are mostly white, yellow and other light colors. In some saline-alkali areas, there is often a layer of white saline-alkali on the soil surface.





4. Judging acidic and alkaline soils by hand feeling



The acidic soil is usually soft in hand, and it is easy to disperse and not easy to cake when it is loosened; the alkaline soil feels firm when it is held in hand, and it is easy to cake but not to disperse when it is loosened.





5. Judging acidic and alkaline soils by the state after watering



After watering, acid soil infiltrates faster, without white bubbles, and the water surface is muddy; after watering alkaline soil, infiltration is slower, the water surface is white bubbles and foams, and sometimes there is a layer of white alkaline substances on the surface.





6. Judging acidic and alkaline soils by texture



The alkaline soil has loose texture, strong permeability and water permeability; the acidic soil is hard and easy to agglomerate, and the soil is easy to agglomerate.



7. Judgment of acidic and alkaline soils by pH test paper