The big picture: using wildflower strips for pest control
A major four-year study across English farms has found that nature-friendly agroecological practices can enhance biodiversity and boost some crop yields, but high costs and land-use trade-offs mean most approaches remain financially unviable without government support.
The research, conducted on 17 commercial arable farms in England, tested how far farmers could reduce their reliance on agrochemicals by using ecological interventions such as wildflower margins, cover crops, and soil enrichment to restore nature’s regulating services—like pollination and pest control.
Farms trialled three systems: standard "business-as-usual" (BAU) methods; an "Enhancing Ecosystem Services" (Enhancing-ES) approach using margins and cover crops; and a more ambitious "Maximising-ES" model that added soil organic matter and in-field strips to attract beneficial insects directly into crop zones.
The results were striking. Soils under the Maximising-ES system showed the greatest carbon gains, and both ecological systems saw increases in earthworm populations and beneficial predatory and pollinating insects. Pollination and pest control services improved significantly, and pest snail biomass dropped in the ecologically managed plots.
Cereals and oilseed rape yields also rose under these nature-based systems. However, the financial picture was less positive. The higher yields failed to compensate for the land taken out of production and the upfront costs of ecological enhancements. Only the moderate Enhancing-ES system broke even—and only with agri-environmental subsidy support.
UKCEH ecologist Dr Ben Woodcock, who led the study, published in the Journal of Applied Ecology, explained, “Without the introduction of new financial incentives, many farmers will be deterred from adopting agroecological farming practices and systems. This could leave them locked into high input, intensive farming systems and more exposed to the impacts of pesticide resistance, declining soil health and climate change.
Scientists at UKCEH and Rothamsted worked with farmers to co-develop the trials using simple management practices within three different agricultural systems on each of the farms:
1) Business-as-usual – typical intensive agriculture and no nature-friendly farming.
2) An 'enhanced' ecological farming system which involved planting wildflower field margins to provide habitat for bees, beetles and spiders, and sowing overwinter cover crops to capture carbon and retain nutrients in the soil.
3) A ‘maximised' ecological system which added to the enhanced system by also planting in-field strips of wildflowers – ‘stripey fields’ – to provide ‘runways’ for beneficial insects to get further into crops, and the addition of organic matter in the form of farmyard manure to improve soil health.
The study found that in the enhanced and maximised ecological systems, there were increased populations of earthworms, pollinators such as bees and hoverflies, as well as natural predators of crop pests such as ladybirds, lacewings and spiders. This reduced populations of pest aphids and snails, and increased the seed numbers and thereby yield of flowering crops like oilseed rape.
There was also higher soil carbon and overall increased crop yields on the farmed area due to healthier soils, greater pollination and natural pest control. The study also found the enhanced ecological system was as profitable as intensive farming, but only due to agri-environmental subsidies.
While the various benefits for biodiversity, soil carbon and yield were greater in the maximised ecological system – which included planting in-field wildflower strips and buying in farmyard manure – the study found that the average farm would require increased subsidies to make it as profitable as intensive farming. Though the additional cost can be offset in certain situations because, for example, mixed farms already have free and easy access to manure.
Our analysis has shown that realising these benefits will require additional support for farm businesses that currently operate on very narrow profit margins
“While farmers run businesses that need to be profitable, there is an increasing awareness that more sustainable systems can help ‘future-proof’ their farms in terms of soil health, less reliance on pesticides and climate change, said Woodcock.
“Agroecological methods are good for biodiversity, food security and, in the long-term, provide more secure farm incomes but habitats can take several years to establish, so agri-environment subsidies are essential to helping farmers transition to these more sustainable systems.”
The study authors say demonstrating the effectiveness of agroecological practices to farmers could be a critical step breaking farmers free from 'intensification traps'.
Rothamsted's Professor Jonathan Storkey, one of the co-authors, said: “This study confirmed that managing land on farms for wildlife is not in direct conflict with food security but can support sustainable production by increasing yields and reducing pest pressure. These ‘ecosystem services’ could potentially substitute for chemical fertilisers and pesticides which negatively impact the environment.
“However, our analysis has shown that realising these benefits will require additional support for farm businesses that currently operate on very narrow profit margins. As input costs increase, however, these agroecological approaches may become more attractive.”
Plant Ecologist
Rothamsted Research is the longest-running agricultural research institute in the world. We work from gene to field with a proud history of ground-breaking
discoveries in areas as diverse as crop management, statistical interpretation and soil health. Our founders, in 1843, were the pioneers of modern
agriculture, and we are known for our imaginative science and our collaborative approach to developing innovative farm practice.
Through independent research, we make significant contributions to improving agri-food systems in the UK and internationally, with
economic impact estimated to exceed £3 bn in annual contribution to the UK economy. Our strength lies in our systems approach, which combines strategic research,
interdisciplinary teams and multiple partnerships.
Rothamsted is home to three unique National Bioscience Research Infrastructures which are open to researchers from all over the world:
The Long-Term Experiments,
Rothamsted Insect Survey and the
North Wyke Farm Platform.
We are strategically funded by the Biotechnology and Biological Sciences Research Council (BBSRC), with additional support from other national and
international funding streams, and from industry. We are also supported by the Lawes Agricultural Trust (LAT).
The Biotechnology and Biological Sciences Research Council is part of UK Research and Innovation, a non-departmental public body funded by a grant-in-aid
from the UK government.
BBSRC invests to push back the frontiers of biology and deliver a healthy, prosperous and sustainable future. Through our investments, we build and support a vibrant,
dynamic and inclusive community which delivers ground-breaking discoveries and develops bio-based solutions that contribute to tackling global challenges,
such as sustainable food production, climate change, and healthy ageing.
As part of UK Research and Innovation (UKRI), we not only play a pivotal role in fostering connections that enable the UK’s world-class research and innovation system
to flourish – we also have a responsibility to enable the creation of a research culture that is diverse, resilient, and engaged.
BBSRC proudly forges interdisciplinary collaborations where excellent bioscience has a fundamental role. We pioneer approaches that enhance the equality, diversity,
and inclusion of talent by investing in people, infrastructure, technologies, and partnerships on a global scale.
The Lawes Agricultural Trust, established in 1889 by Sir John Bennet Lawes, supports Rothamsted Research’s national and international agricultural science through the provision of land, facilities and funding. LAT, a charitable trust, owns the estates at Harpenden and Broom's Barn, including many of the buildings used by Rothamsted Research. LAT provides an annual research grant to the Director, accommodation for nearly 200 people, and support for fellowships for young scientists from developing countries. LAT also makes capital grants to help modernise facilities at Rothamsted, or invests in new buildings.