A qualitative and quantitative survey was made of the aerospora above an Eragrostis curvula (Schrad.) Nees pasture. The pasture, which lay adjacent to a field of Panicum coloratum L. where an outbreak of ovine photosensitivity had occurred, was not grazed during the survey. A Burkard volumetric spore trap was used to sample the aerospora continuously for 10 months. Twenty components of the aerospora were recognized: spores of 9 genera of fungi (Cladosporium, Alternaria, Epicoccum, Drechslera, Pithomyces chartarum (Berk. & Curt.) M. B. Ellis, Nigrospora, Sporormia, Curvularia, Spegazzinia); 8 recognizable but unidentified spore types; rust spores; hyphal Fragments and pollen grains. Cladosporium conidia comprised 83,37% of the total aerospora. Conidia of Pithomyces chartarum formed a small (0,29%) but significant component of the aerospora, since this fungus is known to cause hepatogenous photosensitivity.