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In this Farm Net Zero field lab, nine Cornish farmers are trialling different ways of managing their grassland to reduce docks without using herbicides.
The triallists will be applying calcium and carrying out different mechanical interventions to reduce soil compaction.
The idea came from the work of James Barrett of Tremadart Barton who demonstrated how he managed docks without agrochemicals. James demonstrated his technique as part of a Farm Net Zero event in 2023.
This field lab is funded through the Community Lottery Funded Farm Net Zero Project.
Docks are perennial weeds that often grow in grassland. They can spread quickly as they produce a huge quantity of seed, and can quickly establish themselves thanks to their deep-rooted tap root.
Docks are thought to be particularly prevalent in compacted soil conditions and in soils which are low in calcium.
It is hoped that by improving soil structure and chemistry in grassland farmers can reduce their dock burden without the use of herbicides.
Each farm will dedicate one field to the trial.
Step 1: The researcher will assess the depth and severity of soil compaction in the trial fields, and recommend the appropriate mechanical intervention (eg subsoiler / slitter). Soil assessments will determine soil calcium levels and pH.
Step 2: The trial field will be split into 4 areas: 1) No intervention (control); 2) Calcium only; 3) Mechanical intervention only; and 4) Calcium and mechanical intervention.
Step 3: The farmers will graze/cut the field according to standard management. Mid season a foliar sample of the grassland will be taken from the area with calcium and the area without calcium. If deficiencies are evident, further calcium application will be carried out.
Step 4: At the end of the season, assessment of dock density will be assessed, and soil structure.
Wet weather delays some of the aeration treatments
The original plan to carry out all the mechanical treatments before Christmas was unfortunately scuppered by very wet autumn weather. So four of the farmers have carried out both mechanical aeration and applied the calcium. The rest will endeavour to carry out the work in the springtime.
This has highlighted that many farmers do not possess the equipment to carry out the aeration work, and the pressure of finding a weather window when a contractor is able to carry out the work. It could allow an insight into whether autumn or spring aeration work better for compaction treatment - though this will be very much weather dependent!
The overall trial timeline has not changed, as the assessments will still be carried out at all farms in the summer.
May 20204
June 2024
June 2024
June 2024
Oct-Nov 2024
Jan - Feb 2025
Trifolium Services
Southwest England
Hannah Jones has previously coordinated and carried out research projects spanning herbal leys, arable systems, cover crops and field vegetables. Her role has been to coordinate farm-based trials by working closely with farmers and agricultural businesses to optimise the impact and applicability of the research. She has a PhD in plant pathology from Oxford University, a degree in plant sciences from Birmingham University, a Masters in postgraduate teaching from the University of Reading, and is FACTS qualified.