Black truffle soil characteristics
Most of parameters before analyzed for truffle farming are not bearing in mind nowadays. Texture, carbonates, iron, magnesium, potassium...have great variability. Actually the soil structure trough the study of the horizons and the biological activity are more studied.
So to know if we can grow truffles on a soil we should study the horizons, confirm the presence of carbonates and analyze the pH (that should be between 7.5-8.5). Soil should not be water Proof, allowing water and air to drain trough.
To check if the soil has carbonates we can just drop diluted clorhidric acid and see that the soil boils (effervescence).
Should not have discontinuities between layers, with some difficult to mark limits between them.
Crumble structure and spherical particles. Avoid prismatic structures, sign of lixiviation. Laminar structures shows compactation and flood. Bad soil structures get grooved and heavy on dry weather.
Some grey and green colours on the soil profile mean bad drainage.