13
Sep
Bees Benefit from Diverse Flower Species in Ag Fields and Surroundings; Organic Farm Benefits Highest
(Beyond Pesticides, September 23, 2024)Â While chemical companies persist in pushing simplistic solutions to complex problems, there is a large amount of evidence that organic farming presents effective solutions to many of those problems. Now there is new evidence that organic agriculture prevents the untold harms of pesticide-driven monoculture. In a new study, German researchers compared 16 agricultural landscapes in Lower Saxony and northern Hesse that had different combinations of semi-natural habitat, organic practices, and annual and perennial flower strips. Overall, the researchers find that organic farming provides the highest benefit to the bees, along with the presence of diverse flowering plants in and near monoculture fields.
The study compares the effects of three honey bee conservation methods on the prevalence of the parasitic mite Varroa destructor and the 11 parasites Varroa transfers to bees, and the impact of these destructive organisms on bee colony growth. The findings were reported in the June issue of the Journal of Applied Ecology.
Organic practices lead directly to lower parasite load and higher colony growth—essentially, the more organic crops, the more bees, and the more parasites, the fewer bees. Pesticides plus monoculture doubles the damage: Pesticides increase mortality, damage bees’ immune systems, and reduce foraging capacity, while monoculture disturbs bees’ nutritional balance, making them less able to resist parasites and survive pesticide exposure.
In a perverse irony, conventional agriculture has been shifting toward more pollinated crops. Beyond Pesticides has covered research showing that between 1961 and 2016, the aggregate land area of crops requiring pollination grew by 136.9%, all while actual pollinator abundance was plunging because of pesticides, land use and climate changes, and monoculture. Yet the chemical company persuaders push the very practices that are causing the problems. In part, as noted in a 2019 study analyzed by Beyond Pesticides, the jump in pollinator-requiring crops is because they have higher market value than non-pollinated crops like cereals. Oilseed has been a particularly fast-growing sector. That 2019 study also found that crop diversity has not increased with the expansion of pollinated species. Like the larger effect of general biodiversity, crops diversity provides a much better environment for pollinators.
After organic practices, honey bee health depends on flower diversity in nearby semi-natural habitats and non-crop strips alongside fields. The health of European honey bees sometimes appears at odds with that of other wild pollinators, because of a disparity between perennial and annual flowers. Honey bees do better in the study from access to annuals and had higher parasite loads when semi-natural habitats and flower strips were dominated by perennials. This is likely because perennials produce fewer flowers than annuals, crowding more bees into smaller spaces. Further, annuals are associated with lower numbers of Varroa. This is important because, while Varroa directly harms bee health, the numerous other parasites such as viruses that Varroa harbors and transmits may cause even more damage. Yet, other wild pollinators need perennials more, and the authors stress that all insect types benefit from the provision of diverse flower species in fields and their surroundings. Â
Other research has shown that large fields of flowering plants, such as oil rapeseed (the parent plant of canola), attract bees and support colony growth, but also increase parasite loads. They do create masses of flowers that attract masses of insects. They may offer a large amount of food but only for short periods. In fact, previous research has shown that mass-flowering monoculture increases the exposure of bees to parasites, and that “monoculture alone cannot support healthy bees.†Buffer zones like semi-natural habitats and flower strips featuring mixed flowers that bloom at different times provide more stable, long-lasting food supplies.
Both wild pollinators and honey bees are suffering deep losses, and restoring varied landscapes with both perennial and annual flower varieties would help everyone, including farmers. The rationale advanced by some that monoculture of flowering crops by itself will rescue pollinators is wrong, say the authors: “We also found that the relationship of colony growth and parasitism to organic farming is not driven by mass-flowering crops, but rather by a complementary effect of mass-flowering and non-mass-flowering organic agriculture.†Although they did not specify what other organic practices contribute to bee health, there is surely much less stress on pollinators in an environment without pesticides that includes all varieties of biodiversity.
The authors note that their results support the European Union’s Green Deal, which aims to reach 25% organic agriculture in Europe by 2030. A 2023 evaluation of U.S. organic farming compares the success of U.S. policies to those of Denmark. The U.S. came out the clear loser. In 2022 the U.S. Department of  Department of Agriculture (USDA) created an “Organic Transition Initiative†to help reverse the trend that “the number of non-certified organic farms actively transitioning to organic production dropped by nearly 71 percent since 2008,†according to the U.S.D.A. press release. This drop occurred even as demand for organic products doubled between 2013 and 2023. Assessment of the Organic Transition Initiative’s success so far is scarce, but organic advocates praised the initiative when it was announced because it aims to provide mentors, extension agents and crop advisors with organic expertise to farmers transitioning to organic practices.
Everyone can contribute to the shift away from our toxic “business as usual†approaches and toward a genuinely sustainable agroeconomy. As set out in the June 18, 2019 Beyond Pesticides Daily News entry, “through public pressure and consumer choice, we can shift towards alternative products and practices, improve biodiversity, and begin to repair the damage done by industrial agriculture.†You can track pollinator, biodiversity, and organic agriculture developments with Beyond Pesticides’ multiplicity of tools, including our Daily News and the journal Pesticides and You. Support our work by becoming a member and/or signing up to learn about actions to take in support of our mission.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Sources:
Organic farming and annual flower strips reduce parasite prevalence in honeybees and boost colony growth in agricultural landscapes
Patrycja Pluta et al.
Journal of Applied Ecology
June 2024Â
https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2664.14723
Global agricultural productivity is threatened by increasing pollinator dependence without a parallel increase in crop diversification
Marcelo A. Aizen, et al.
Global Change Biology
July 10, 2019
https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.14736
European Commission: Directorate-General for Environment, Agri-environment schemes – Impacts on the agricultural environment
Publications Office, 2017
https://data.europa.eu/doi/10.2779/633983 Â Â
Industrial Agriculture Practices Contribute to the Insect Apocalypse
June 18, 2019
https://beyondpesticides.org/dailynewsblog/2019/06/industrial-agriculture-practices-contribute-to-the-insect-apocalypse/
Monoculture in Crop Production Contributes to Biodiversity Loss and Pollinator Decline
Beyond Pesticides, July 26, 2019
https://beyondpesticides.org/dailynewsblog/2019/07/monoculture-in-crop-production-contribute-to-biodiversity-loss-and-pollinator-decline/
Study of Pesticide Risk in Wild Bee Species Highlights EPA Risk Assessment Inadequacies
Beyond Pesticides, August 23, 2024
https://beyondpesticides.org/dailynewsblog/2024/08/study-of-pesticide-risk-in-wild-bee-species-highlights-epa-risk-assessment-inadequacies/
Neonicotinoid Insecticides Contribute to Honey Bee Vulnerability to Parasitic Varroa Mites
Beyond Pesticides, July 10, 2024
https://beyondpesticides.org/dailynewsblog/2024/07/neonicotinoid-insecticides-contribute-to-honey-bee-vulnerability-to-parasitic-varroa-mites/
Mass-flowering monoculture attracts bees, amplifying parasite prevalence
Hamutahl Cohen et al.
Proceedings of the Royal Society B
October 13, 2021
https://royalsocietypublishing.org/doi/10.1098/rspb.2021.1369
