Management practices to increase deep burrowing earthworm numbers, crop rooting depth and yields

This field lab will study how crop yield, root depths and earthworm numbers are impacted by additions of organic matter in no-till, strip-till and conventional cultivation.

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Field Lab Timeline

    11/19/2019 12:00:00 AM
  • Member gathering at YEN Awards

    Member gathering at YEN Awards
  • 2/6/2020 12:00:00 AM
  • Final meeting from previous project

    Final meeting from previous project
  • 3/30/2020 11:00:00 PM
  • On-farm assessments

    On-farm assessments
  • 6/14/2020 11:00:00 PM
  • On-farm assessments

    On-farm assessments
  • 6/14/2020 11:00:00 PM
  • Group meeting & results discussion from spring assessments

    Group meeting & results discussion from spring assessments
  • 8/29/2020 11:00:00 PM
  • Harvest assessments

    Harvest assessments
  • 9/9/2020 11:00:00 PM
  • Data analysis

    Data analysis
  • 11/15/2020 12:00:00 AM
  • Results meeting

    Results meeting
  • 12/15/2020 12:00:00 AM
  • Final report published

    Final report published
For further information hover over the above milestone marks
  • Discussion

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  • Achievements

    February 2021

    Final report published

    The final report, including details on the individual trials, has been published in the Documents section above (sign-in required, registration is free).


    • Soil organic matter was notably high for plots with added manure.

    • Soil structure (assessed visually) was very similar across treatments, however differences would only be expected to show after several years.

    • Earthworms were particularly abundant in plots which were treated with farmyard manure additions. This is because added farmyard manure provides a food source for the earthworms.

    • Visual assessments showed a lot of evidence of oilseed roots growing down earthworm channels, up to depths of 90cm.

    • The group is interested in doing further research to see if deeper crop rooting from utilising earthworm burrows has allowed more access to water and nutrients, thus positively impacting yields.

    Farmer A (based in Shropshire), who owns beef cattle but previously only applied manure on 25% of the arable crops, noted: "...the research has proved that manure is a definite positive upon the soil, the worm populations and upon the crop yield. It has had the biggest effect compared to cultivation. The trial on my farm seems as you would expect- but the other farms have not had the same results."

    Milestone: Final report published

    November 2020

    Harvest yield results

    Initial yield results from the three farms do not indicate a notable impact on yield from the different treatments. The researcher explained that this is not surprising, as we would expect any increases in anecic (deep-burrowing) earthworm populations to take place slowly, so only after several years would the effects on rooting, yields and soils be apparent.

    Full results to come shortly...

    Milestone: Harvest assessments

    March 2020

    Trial design

    Each farmer has picked soil management practices that were relevant to their farming system, such as deep cultivation, strip till, direct drilling, but always included with or without farm yard manure.

    They set up different tramline trials (with some choosing to run replicated trials) in order to test the impact of these different soil management practices.

    All the farmers grew winter oilseed rape for the trial.

    Example layout from farmer A:

    • Strip till
    • Deep Cultivation
    • Deep cultivation + FYM
    • Strip till + FYM

    • Counts of earthworms and middens. Middens are small accumulations of digested/plant material above the burrow of a deep-burrowing earthworm
    • Visual evaluations of topsoil and subsoil structure
    • Yield map data
    • Visual assessments of rooting in 1 metre deep soil pits

    Milestone: Final meeting from previous project

    February 2020

    Group meeting

    The final meeting from the EIP-Agri funded Yen Yield Testing project took place in Kettering. Results from the 2019 trials run by Deeper Rooting Field Lab members were presented to farmers.

    In the previous trial, the group found that worm counts thrived with farmyard manure applications and shallow or no cultivations. However, increased yields when using manures may be a result of the extra nutrition from the manure rather than from the worms and fewer cultivations.

    Milestone: Final meeting from previous project

    November 2019

    Post-meeting gathering

    The group for this field lab formed out of an earlier project that was co-founded with ADAS researchers. They ran trials in 2019 and met in November to discuss their experiences of the trial and the results.

    The group currently consists of four farmers, of which three are keen on continuing into a second year of testing and have established the treatment comparisons for this coming season. They maintain an active WhatsApp group for communication.

    Milestone: Member gathering at YEN Awards

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