A floristic survey of the grasses was undertaken in the areas directly and indirectly affected by the Mario Covas ring road, located in the municipalities of Mauá, São Bernardo do Campo and São Paulo, plus 15 other municipalities around São Paulo city. The objectives of the survey were to increase the knowledge of the family Poaceae in these areas, to identify the different threats for the conservation of the local grass flora, and to contribute with data directed towards the restoration of degraded areas. The family is represented by 62 genera and 160 species, including 125 native species (78.1%) and 35 that were introduced (21.9%). Five species were considered threatened with extinction and three new occurrences were recorded for São Paulo State (Reimarochloa acuta, Merostachys kleinii and Sacciolepis indica). It is recommended that the pioneer species should be maintained in the area, as well as that some native species could be introduced to enrich the local biodiversity and to control the invasive species. Research projects involving direct planting of native species as an alternative to the use of Urochloa spp. and Melinis minutiflora (molasses-grass) in disturbed areas are suggested.
grasses; new citations; threatened species
