Challenge:

Modern arable agriculture faces many challenges. Pressure on farmers to increase production while using sustainable approaches and fewer inputs has grown. The sector also needs to meet additional production challenges driven by societal, political, environmental and market pressures. Achieving these ends while maintaining economic viability, resilience, and yield is critical to grower businesses in managing the transition sustainably and successfully.

Study title:

TRansition paths to sUstainable legume-based systems in Europe (TRUE)

Scope:

Legume-supported polyculture can help address some of the key challenges being faced by the sector, and can contribute towards the improvement of soil health, underpinning both productivity and environmental gains. Important management issues, however, need to be addressed, and there is a need for options that can be used across a range of crops. Precision approaches and technologies can play a role in resolving some of these challenges.

The TRUE project, funded by the EU Horizon 2020 programme, brought together a consortium of 24 international partners, including Stockbridge Technology Centre (STC). Over four years, a transdisciplinary approach was used to explore strategies to reduce dependency on imported protein food and synthetic nitrogen fertilisers, identifying transition pathways to increase sustainable legume cultivation and consumption across Europe and the UK.

Methodology:

As part of their contribution to the TRUE project, STC’s case study sought to explore agronomic and management options of in-crop clover green understories (or ‘living mulches’), to resolve and optimise important crop establishment and clover management issues. The study also validated Precision Agriculture Technologies (PAT) assisted techniques and machinery in a wide range of broad-acre crops to achieve successful intercropping, evaluating crop performance, environmental, soil, and biodiversity indicators to assess management impacts.

In order to deliver the trials, STC made use of the RTK GPS-supported CHAP strip-till cultivator, part of the CHAP Field Scale Precision Equipment suite. The precision strip till allowed soil preparation of strips within young clover living mulches prior to drilling of multiple broad-acre arable crops into the seed bed. This supported crop germination and establishment rates, mitigating competition levels between the crop and clover, while maintaining some of the soil health benefits associated with minimum tillage. Insights on the crop-specific benefits and detriments of different clover species selections, including differences in ability to suppress weed or pest levels, suitability to different crop work techniques, and penalties to yield, were also formed. Overall, the trials successfully showed that PAT-assisted strip tillage in newly sown clover understories can help mitigate yield penalties in most years, where clover competition is low.

In other concurrent trials, input regimes on well-established and mature clover understories showed that in addition to use of strip tillage, knocking the clover back with a broad-spectrum herbicide prior to drilling could help mitigate yield penalties in cereal crops. These can be considerable in some years, particularly when no further inputs are applied (as was the case in these specific trials). Mowing of the clover within growing season is increasingly seen as an important means of clover management, further removing the need for inputs, but doing so within a crop can present a challenge. Initial trials showed that developments in this area would be of benefit. Use of a strip-tillage and mowing treatment regime returned a reduction in yield of only 8% compared to current conventional practice, despite the 50% reduction in seeding rate compared to the conventional area.

Dr Banfield-Zanin noted: “The CHAP strip till allowed us to combine leading-edge machinery and precision agriculture technologies with agro-ecological approaches. By applying high levels of repeatability and accuracy at commercially relevant scales, we have been able to validate and optimise some crop management options in clover living mulch systems to support productivity and soil health. The trials also show that engagement with modern machinery developments can support farmers who are looking to explore how species-diversification within-field might help meet their soil health goals, while also maintaining the productivity, economic viability, and market resilience of their businesses. There are still challenges to overcome and further development is needed, but by using engineering solutions some of the current challenges faced by the arable sector might be addressed.”

Impact:

STC’s TRUE Case Study applied a modern machinery platform and PAT techniques, provided by the Field Scale Precision Equipment, and polyculture practices to optimise and validate crop and clover management options, helping to realise commercially viable living mulch-based crop production systems. By combining developing technologies with the refinement of existing approaches and solutions to crop management, some of the significant issues associated with the use of leguminous living mulches can be addressed. Legume-supported polyculture can play an important role in addressing some of the key challenges and concerns faced by the arable agriculture sector, and this work promotes possible solutions for continued crop productivity across multiple broad-acre crops, supporting growers as they explore tools and options to achieve environmentally responsible sustainable intensification of agricultural production.

Find out more about the author, Dr Jennifer Banfield-Zanin, read her article on Five benefits of adopting intercropping techniques, or have a look at another project:  Precision approaches for sustainable soils.

For more information go to our Field Scale Precision Equipment capability page or visit Stockbridge Technology Centre.  Further details of the project can be visited on the TRUE website