Pastures are not uniform, and recent evidence has revealed that even well managed pastures have patchy distributions of most measurable characteristics. Patterns have been measured at various spatial and temporal scales. Variation in nutrient distribution results from small-scale patches of dung and urine, and larger-scale patches resulting from transfer of nutrients by livestock towards watering and resting areas. Variation in biomass results from patchiness in plant nutrition, patchiness in microbial organisms, as well as unevenness in livestock and insect defoliation. Sward composition is equally variable, with patchiness at various scales in the number and identity of forage and weed species present. Even the simplest of pasture mixtures i.e. the balance between grass and clover, varies with temporal and spatial scale. Recent modeling has been relatively successful in giving improved predictions of this relationship. Animal responses to patchiness are not linear, and spatial patterns in grassland can affect both the total amount and the composition of animal intake. Recent field studies have found that improved livestock performance is possible when spatial patterns of grass and clover are explicitly managed for optimum animal intake.