Rhizosheaths

Rhizosheaths are coatings of soil particles that cling to plant roots, making roots brown instead of white. They are a sign of biological/microbial activity in the rhizosphere (root zone). Soil particles are bound to the roots by biotic glues, secreted by microorganisms. This is aggregation in action and therefore indicates the formation of good soil structure.

Rhizosheath scoring is included for benchmarking & analysis in the Soilmentor Regen Platform.

Rhizosheath development helps plants to cope with water stress, nitrogen and phosphorus deficiencies, and soil acidity. Biology and exudates around rhizosheath can buffer plants up to a pH of 2 units. This zone also provides a buffer against high Al and Na.

N.B. Some species do not form rhizosheaths, such as cultivars in the brassica, allium & asparagus family.

What to record


  • Score
    • 0. None, roots white. No soil covering
    • 1. Some roots coated. Some roots have partial or full coating
    • 2. Most or all roots coated. Most roots are fully coated
  • Photos

Equipment


  • Spade
  • Gloves

How to do the test

1. Locate your chosen sample site – you can use the GPS mapping feature on the app to do this if you’ve recorded the sample locations previously.

2. Dig out a small section of soil, no wider than your spade. Or combine with other spade tests (20cm x 20cm).

3. Break soil away from roots lightly and shake gently so any loose soil falls away.

4. Observe if there is any light soil that seems to be attached around the roots.

5. Record a score of 0-2 in Soilmentor for the amount of roots with rhizosheaths observed and take a photo in the app.