Electrohydrodynamical impedance measurements were performed during tellurium electrodeposition and correlated to the morphology of the deposits as observed by SEM. In particular, when the current is under a pure mass transport control, microdendrites are formed with various shapes depending on experimental conditions. EHD diagrams are then characteristic of a non-uniformly accessible surface. The calculated dimensions of active zones are in agreement with the sizes of the observed dendrite bushes.