Combined PLIF and PIV experiments were performedin the near-wake region of a multi-scale array of three dif-ferent length scales. We document, and measured terms ofthe multi-scale triple-decomposed energy budget and showthe importance of non-linear interactions between the pri-mary shedding structures in multi-scale generated turbu-lence. We subsequently observe a cascade of scalar burstingevents, in which the scalar is transported a large distance inthe transverse direction over a short period of time. Thesebursts unfolded spatially, such that they were observed be-tween the small and medium wakes and the medium andlarge wakes. These bursts were also observed in the wakeof a single-scale array of objects of comparable blockageto the multi-sale array, but there was no cascade of burstsidentified and they all occurred in the same spatial location.Combined, these findings verify the space-scale unfolding(SSU) mechanism originally postulated in Laizet & Vassil-icos (2012). By performing the multi-scale triple decompo-sition of Bajet al.(2015) we show that the dominant modein the scalar transport is that associated to the fundamentalshedding of the larger of the two intersecting wakes. Wethus conclude that the SSU mechanism is subtly differentto that originally postulated by Laizet & Vassilicos (2012).Those authors originally attributed the SSU mechanism tothe coherence of the overall, Reynolds-decomposed veloc-ity fluctuationu′. Here we show that the dominant effect isin fact the coherent part of the fluctuating velocity concor-dant with the fundamental shedding frequency of the largerof the two interacting wakes. Downstream of the wake in-tersection point this particular coherent scalar flux compo-nent is the major contributor to the overall scalar flux.