Meaning of the column names: 
Plant_species: Cyanus segetum (C. segetum) or Centaurea jacea (C. jacea).
Plot_ID: the plot identification number (see Appendix 1, Fig. S2).
X_Coord and Y_Coord: geographic coordinate of each plot (X and Y axes; Appendix 1, Fig. S2).
Plant_ID: Identification number of the plant.
C/N: carbone (C) / nitrogen (N) ratio.
PlantBiomass: The biomass of the whole plant.
Nbr_Flower_heads: total number of flower heads per plant.
Flower_Head_Biomass: Biomass of the total number of flower head per plant.
Nbr_Seed: Number of seed counted per plant.
Seed_Biomass: biomass of the total number of seed collected per plant.
SNH_proportion: proportion of semi-natural habitat (SNH) area within a radius of 300m of each plot.
Floral_Abundance: number of flowers in a 100m transects along field borders centred on each focal plant plot.
Floral_Species_Richness: number of flower species in a 100m transects along field borders centred on each focal plant plot.
Flowering_Crop_proportion: Proportion of flowering crop area within a radius of 300m of each plot.
Flowering_Crop_Species_Richness: Number of flowering crop species counted within a radius of 300m of each plot.
Abondance_pollinator: Number of pollinators observed as pollinating focal plant both in focal plant plots and transects. 
Pollinator_Species_Richness	: Number of pollinator species observed as pollinating focal plant both in focal plant plots and transects.
Tillage: Occurrence of tillage in the adjacent field.
Herbivore_Abundance: Number of seed herbivores (Tephritidae; Diptera) emerged per plant.
Herbivore_Species_Richness: Number of seed herbivore species (Tephritidae; Diptera) emerged per plant.
Parasitoid_Abundance: Number of parasitoids of seed herbivore (Hymenoptera) emerged per plant.
Parasitoid_Species Richness: Number of seed herbivore parasitoid species emerged per plant.
Herbivory_Rate: Calculated as the number of seed herbivore divided by the total number of seeds (estimated as the sum of seeds and herbivores emerging per plant).
Parasitism_Rate: Calculated as the number of parasitoids divided by the total number of potential hosts (estimated as the sum of herbivores and parasitoids emerging per plant).