The environmental impacts of organic agriculture are only partially understood and whether such practices have spillover effects on pests or pest control activity in nearby fields remains unknown. Using about 14,000 field observations per year from 2013 to 2019 in Kern County, California, we postulate that organic crop producers benefit from surrounding organic fields decreasing overall pesticide use and, specifically, pesticides targeting insect pests. Conventional fields, by contrast, tend to increase pesticide use as the area of surrounding organic production increases. Our simulation suggests that spatially clustering organic cropland can entirely mitigate spillover effects that lead to an increase in net pesticide use.
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Identifying and characterizing pesticide use on 9,000 fields of organic agriculture
Abstract Notwithstanding popular perception, the environmental impacts of organic agriculture, particularly with respect to pesticide use, are not well established. Fueling the impasse is the general lack of data on comparable organic and conventional agricultural fields. We identify the location of ~9,000 organic fields from 2013 to 2019 using field-level crop and pesticide use data, along with state certification data, for Kern County, CA, one of the US’ most valuable crop producing counties. We parse apart how being organic relative to conventional affects decisions to spray pesticides and, if spraying, how much to spray using both raw and yield gap-adjusted pesticide application rates, based on a global meta-analysis. We show the expected probability of spraying any pesticides is reduced by about 30 percentage points for organic relative to conventional fields, across different metrics of pesticide use including overall weight applied and coarse ecotoxicity metrics. We report little difference, on average, in pesticide use for organic and conventional fields that do spray, though observe substantial crop-specific heterogeneity.
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- Award ID(s):
- 2042526
- PAR ID:
- 10383731
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 12
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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The environmental impacts of organic agriculture are only partially understood and whether such practices have spillover effects on pests or pest control activity on nearby fields remains unknown. Using roughly 13,000 field observations per year from 2013-2019 in Kern County, CA , we estimate that organic crop producers benefit from surrounding organic fields, decreasing overall pesticide use and pesticides targeting insect pests. Conventional fields, in contrast, tend to increase pesticide use as the area of surrounding organic production increases.more » « less
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