If a plant has a large quantity of soil clinging to its roots, where the roots appear brown and not white, this soil coating is called a rhizosheath.
Why do we love them so much? They are an indicator of life in the soil: of biological and microbial activity in the rhizosphere, which is also known as the root zone.
Micro-organisms feed on root exudates and secrete binding agents which hold soil particles together around the roots in an aggregated structure, which indicates good soil health.
Soil structure is aggregating around the roots (photo from Niels Corfield https://twitter.com/niels_corfield/status/1070304660374855685)
“A simple way to find out what healthy soil looks like in your fields is to pull up some weeds! Don’t be surprised if you find rhizosheaths on these roots; weeds are often the healthiest plants in your soil.” – Niels Corfield, Soil Health Advisor
Watch the video below to find out how to assess rhizosheaths in your soil:
Fred Price, a regenerative farmer, describes how rhizosheaths indicate good soil health: “Seven years ago I didn’t know roots could look like this (see photo below)! The biological component of our soils mediates the soil-plant interface, increasing availability of nutrients and resilience to biotic and abiotic stress. So a well developed rhizosphere, the zone of plant influence in the soil characterised by root exudates, microorganisms and indicated by a healthy rhizosheath, is a great barometer for a highly functioning soil ecosystem. This vitality reduces the need for synthetic inputs, allowing the biological component to flourish further – this positive feedback cycle underpins any regenerative farming system.”
Rhizosheaths at Fred Price’s farm
Soilmentor can be used to monitor the development of rhizosheaths – you can score your progress in the app! Learn more about scoring your rhizosheaths with Soilmentor here.
We plan to develop this scale to be more nuanced, so if you’ve been observing rhizosheaths in your soils we’d love to hear from you about your experience – firstname.lastname@example.org.
See our free online soils guide for soil tests you can do at home and find out how our app Soilmentor helps you record & learn how your soil is changing.