Fig. 4. Distribution of field beans (Vicia faba) and oilseed rape (Brassica napus) in the UK and their presence within honey samples (n = 424) detected using DNA metabarcoding.

The distribution of field beans (a) and oil seed rape (b) in 2017 from CEH Land Cover plus: Crops map is shown under honey samples with Vicia spp. (a) and Brassica spp. (b) present, as indicated by coloured squares. Black circles: not detected. c Vicia spp. were more likely to be detected in honey within a 2 km radius of field beans (x² = 52.83, d.f. = 4, p < 0.0001) and Brassica spp. within 2 km of oil seed rape (x² = 50.71, d.f. = 4, p < 0.0001) (Supplementary Table 1).