Representative 3D renderings of root systems grown in repacked soil columns.

<p>(A) tillage radish after 20 days growth; (B) tillage radish after 58 days growth; (C) vetch after 20 days growth; (D) vetch after 58 days growth; (E) black oat after 20 days growth; (F) black oat after 58 days growth. Red arrows indicate location of change in dry bulk density of soil profile from 1.2 to 1.4 g cm<sup>-3</sup>.</p>