A comparison was made of the mycofloras on freshly harvested barley and on barley stored in farm or laboratory silos. There were few differences in the mycoflora at harvest on samples from five sites. In farm silos field fungi were replaced by storage fungi which included Candida spp. and Hansenula anomala, accompanied by Penicillium roquefortii in the four silos with moisture contents (mc) mostly above 19%. Later, Absidia, Aspergillus, Mucor and Penicillium species grew. In laboratory silos, field fungi died out after about 100 days at mc's over 20%, pink field yeasts had survived for about 300 days at 15–16 % mc, but no storage fungi grew.