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Earthworms influence infiltration and solute transport in agricultural soils developed on glacial till - a widespread parent material across the Northern Hemisphere. Their burrowing activity enhances soil structure and generally improves water infiltration while reducing surface runoff. However, their burrows can function as preferential flow paths, potentially accelerating the leaching of nitrates and pesticides to groundwater under certain conditions. At the same time, the microbiome of the drilosphere can adsorb, retain, and degrade solutes. This study maps the spatial structure of earthworm burrows in a Danish field under winter wheat and annual crop rotation from 2011 to 2014. Macropore connectivity and preferential flow potential were assessed using horizontal excavations and macropore mapping in vertical profiles, Brilliant Blue dye tracing, and surface smoke tracer tests. The earthworm community was dominated by anecic species (<i>Lumbricus herculeus</i> and <i>Aporrectodea longa</i>) which maintain deep vertical burrows that enhance hydrological connectivity. Stable isotope analysis confirmed distinct ecological categories among the four species, consistent with their feeding types and ecological traits relevant to burrow formation. Following a transition from conventional to reduced tillage, we observed a marked increase in surface-connected burrows and their hydrological connectivity, indicating recovery of earthworm-mediated infiltration pathways. The density of Brilliant Blue-stained earthworm burrows - indicating hydrologically active flow paths - remained stable down to 2.0 m depth, whereas unstained burrows declined sharply with depth. This contrast shows that only a subset of earthworm burrows remains functionally connected to infiltrating water at depth, supporting the interpretation that anecic earthworm burrows constitute dominant preferential flow paths. These findings highlight the functional role of earthworm burrows in structured glacial till soils, with important implications for groundwater recharge and solute transport.