User

Soil intermediate

Difficulty/Levels

Level 2

Data Type

What is the meaning and importance?

Soil colour is given by a combination of organic matter and minerals in the soil. Color alone can give a lot of information about the soil type and its fertility. Without any chemistry lab, the soil colour alone can already tell us about what’s in the soil at the microscopic level. The amount of organic matter in a soil can tell us whether the soil is acting as a carbon sink or not.

What is the method for collection?

  1. Check if there is a clear difference between topsoil and subsoil after digging the ~20 cm hole
  2. Scoop two separate samples from each horizon (if two are present, otherwise take one sample).
  3. Observe each soil horizon separately against a solid coloured background (e.g. piece of plain paper). Also compare the soil colour to ~12 other colours (brown, black, red, yellow, etc.)
  4. Select the closest match.

How long does it take to collect?

5-10 minutes: One data point if only topsoil, two data points if there is a clear different coloured subsoil present

Evaluation Parameters

(If applicable: 1=good; 2=fair; 3=poor)

Assign a colour to the soil. You can choose between:

(a) Dark black (b) Light black (c) Dark brown (d) Light brown (e) Dark red (f) Light red (g) Orange (h) Yellow (i) Dark green (j) Light green (k) Blue (l) Gray

Alternatively, you can use the Soil Color Chart provided in the pictures below and just use the letter which is linked to the colour (e.g. a for black, h for yellow, etc.).

Toolkit