Fig. 2. Minirhizotron images showing canola roots growing in May (left) and soybean roots observed in July and August (right) following the channels made by the preceding canola cover crop at 38.2 cm (at WREC) (top) and 18 cm (at BARC) (bottom) depth. Bulk density was 1.55 and 1.61 and penetration resistance was 2247 and 2176 kPa for the upper and lower soils, respectively.