Transfer of mass between macropores and the soil matrix is an important control on flow and solute transport in the vadose zone. Few empirical techniques are available to explicitly investigate how the fast flows in macropores interact with the slower flows in the matrix to allow the flow system to evolve over time. In this study, time-lapse X-ray Computed Tomography (CT) scans are used to obtain quantitative 4D (i.e., transient three-dimensional) images of infiltration in two soil columns: one homogenous, non-macroporous and one containing a network of desiccation cracks. Water was applied to the top of each column at increasing rates over the flow period. High resolution (80 micron) CT images of the columns were collected throughout the infiltration experiments at 7-minute intervals. These images were processed to obtain time-varying maps of water content that provide insights to the evolution of the flow patterns and mechanisms of interaction between the macropore and matrix domains. Flow in the non-macroporous column was observed to be nearly uniform, whereas flow behavior in the macroporous column was dependent on the influent water flux. At low infiltration rates, film flow occurred in the macropores with comparatively little imbibition from macropore to matrix. At high infiltration rates, the macropores filled with water and imbibition to the matrix increased. Results demonstrate that wetting of the soil is a complex process reflecting contributions from downward infiltration through macropore-matrix networks and lateral wetting from the macropores.