This paper incorporates the indigenous ecological knowledge (IEK) of the Maasai pastoralists and ecological methods to assess e¡ects of grazing and cropping on rangeland biodiversityat macro-and micro-landscape scales in northernTanzania. The joint surveys with pastoralists identi¢ed indicator plant species and their associations with micro-landscapes and livestock grazing suitability (i.e. for cattle and small ruminant grazing), while traditional calf-pasture reserves (alalili pl. alalilia) were evaluated for preservation of rangeland biodiversity. The macro-landscapes comprising the cool high plateau (osupuko pl. isipuki) and montane forest highland (endim) were included in the survey. At micro-landscape scales, the osupuko was classi¢ed into uplands (orkung'u), slopes (andamata) and dry valley bottomlands (ayarata). The micro-landscapes were assessed in terms of herbaceous plant species and woody species richness and risks of soil erosion. Biodiversity varied at both the macro-and micro-landscape scales and in accordance with the land-use types. Greater plant species diversity and less erosion risks were found in the pastoral landscapes than in the agro-pastoral landscapes. The calf-grazing pastures had greater herbaceous species richness than the non-calf pastures, which inturn had more woody species. The study concludes that the indigenous systems of landscape classi¢cation provides avaluable basis for assessing rangeland biodiversity, which ecologists should incorporate into ecological surveys of the rangelands in East Africa in the future.