The threat that plant diseases and pests pose to food production and ecosystem services is neither well understood in the social sciences nor publicly debated, despite the fact that it is significant and growing. This paper presents findings from interviews with wheat and potato growers
in two parts of the UK (Lincolnshire and Herefordshire). It uses conceptual work on risk and risk perception to understand how farmers encounter, comprehend and manage plant disease. Plant disease was perceived by growers as a significant but controllable risk mostly through the (generally)
prophylactic use of spray chemicals. The introduction of revised European legislation governing – and potentially restricting – the use of ‘key’ agro‐chemicals may, in the future, reduce the perception and level of control growers feel they have over disease
in their crops. Perceptions of plant disease risk and strategies to ameliorate their impact involve scientific deliberation and appear to be highly rational. However, such perceptions are not merely conceived in scientific terms. Decisionmaking is rational but encultured as a practical farm
management priority rather than pure scientific risk.