Fig. 2. Distribution of out-crossing values and management variables for the 315 seed production fields analyzed from 1998 to 2000. A: out-crossing values for all sampling locations. B: isolation distances between seed fields and nearest adventitious pollen source. C: seed field sizes. D: adventitious pollen source field sizes. E: number of border rows. F: male/female row ratios. Distributions of the management variables (B–F) were used to define predictor classes for comparison of out-crossing percentages at the field margins and field midpoints.