Auxin leaks out of the stele via the apoplast.

(A) A diagram showing the orientations used in depicting the fluxes. Angular position is measured counter-clockwise from the line labelled 0°. Negative radial fluxes are inwards; positive are outwards. Negative angular fluxes are clockwise; positive are counter-clockwise. (B) The auxin flux integrated across the cells in each tissue layer. (C, D) Heatmap of auxin levels in the stele of (C) static and (D) dynamic simulations of wol. (E, F) Zoomed-in quadrant of the heatmap of the (E) static and (F) dynamic simulations of wol to facilitate comparison of apoplastic auxin levels.