The scale of spatial heterogeneity in soil nitrogen (N) concentrations varies considerably in grazed systems, because grazers vary in the volume of urine they excrete. This could affect how urine-N is processed, and subsequently how much N is lost from the system, as diffusion and plant effects on soil nutrient concentrations can be scale-dependent. Two field experiments were performed; one measured the impact of urine patch size (small, medium or large) on soil inorganic N pools and fluxes over time, and the other assessed whether urine patch size affected plant responses and system N retention even if the same total amount of urine was applied. Soil from inside small urine patches retained inorganic N for shorter amounts of time, resulting in lower plant biomass and N uptake than that inside larger patches. Although system nitrogen retention was not affected by patch size, it appeared that larger patches had a greater potential to lose N due to the longer period over which soil inorganic N concentrations remained high. This suggests that systems grazed by larger organisms are more prone to lose N through patch size effects than those grazed by smaller ones.