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Small-scale dye experiments estimated infiltration spatial variation, and compared it to previously measured variations in the distribution of atrazine residue in the 0-10 cm layer. Infiltration variation was estimated by measuring dye concentration in soil samples from the 0-3, 3-6, and 6-10 cm depths of the test volume. Contour maps estimated the percentage of infiltration area with a higher than average concentration. Results indicate that: 1) average dye concentration in the upper soil layers was higher and less variable than middle and lower layers; 2) most of the solution passed through 23% of the infiltration area, and 3) variation is greater for infiltration than atrazine residue for this field. This suggests that, under ponded infiltration, preferential flow rapidly began to affect the distribution of infiltrating water. In addition, the variation in atrazine residue may be driven by infiltration variation, however the effect is likely dampened by sorption and/or dissipation processes.