Subsurface injection of animal manure is a best management practice (BMP) that reduces odors and promotes efficient nutrient usage. In tile‐drained fields, however, injected wastes have been observed emerging from tile outlets shortly after application. This appears to be a particular concern in no‐till fields where Lumbricus terrestris L. are often numerous. Our objective was to determine if burrows created by this earthworm species can contribute to rapid movement of injected wastes to tile drains. A turbine blower was used to force smoke into a 0.6 m‐deep tile line in a no‐till field and 20 burrows 0.02 to 0.5 m from the tile that emitted smoke, and 18 burrows 0.8 to 4.7 m from the tile that did not produce smoke were flagged. A Mariotte device filled with dyed water was then used to measure infiltration rate for each burrow. Afterwards, plastic replicas of the burrows were made so their proximity to the tile and geometrical properties could be determined. Average infiltration rate for smoke‐emitting burrows (128 mL min−1) was twice that of the more distant burrows. Moreover, dyed water was observed in the tile when added to smoke‐emitting burrows, but not when added to burrows that did not produce smoke. Thus, earthworm burrows in close proximity to tile lines may expedite transmission of injected wastes offsite. Movement of injected wastes to tiles via earthworm burrows and other preferential flow paths may be reduced by using precision farming to avoid waste application near tile lines or by modifying application procedures.

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Previous research has established that macropores can rapidly transmit water through soil. This observation has raised concern that macropores may also promote rapid movement of agricultural chemicals to groundwater. This is a particular concern for no‐till fields where lack of disruption by tillage can lead to the development of extensive macropore systems. In order to investigate the effect of initial rainfall on chemical transport, strontium bromide hexahydrate (SrBr2·6H2O) and atrazine (2‐chloro‐4‐ethylamino‐6‐isopro‐pylamino ‐s‐triazine) were surface‐applied to six 30 by 30 by 30 cm blocks of undisturbed soil obtained from a 25‐yr‐old, no‐till corn (Zea mays L.) field with evidence of well‐defined macropores attributable to earthworm activity. Half of the blocks then received a 1‐h 5‐mm simulated rain, which did not produce percolate. Two days later, the blocks received a 0.5‐h 30‐mm simulated rain, followed by another 0.5‐h 30‐mm rain 1 wk later. The remaining blocks received only the two 30‐mm events. An average of 12% of the applied water passed through all the blocks during and shortly after the first 30‐mm rain. Bromide, Sr, and atrazine losses in this percolate were 7, 10, and 2 times less, respectively, from blocks that received the 5‐mm rain than from blocks not receiving this initial, light rain. The second 30‐mm rain on the blocks not receiving the initial 5 mm produced 1.6× more percolate than the first 30‐mm rain. Yet, transport and flow‐weighted average concentrations of Br, Sr, and atrazine were all reduced. These results indicated that the first storm after application can move solutes into the soil matrix, thereby reducing the potential for transport in macropores during subsequent rainfall events.