A total of thirty-five species of fungi assigned to twenty-eight genera has been isolated from various parts of plants of genus Rosa in the Ottawa area.

Common saprophytic fungi recovered were species of Alternaria, Botrytis, Fusarium, Trichoderma, Pullularia, Penicillium and Aspergillus. Parasitic fungi, known to cause important diseases of rose, were also found including Seimatosporium lichenicola (Cda) Shoemaker and E. Muller (die back), Coniothyrium rosarum Cke. and Harkn. (Canker), Marssonina rosae (Lib.) Lind. (leaf spot), Sphaerotheca sp. (powdery mildew). Species not previously reported as parasites on Rosa have been recovered from this host, namely; Nigrospora sphaerica (Sacc.) Mason, Microascus schumacheri (Hans.) Curzi, Gonatobotrys simplex Cda, and Pseudozythia pusilla Hoehn. Other noteworthy fungi isolated from various plant parts were species of Chaetomium, Curvularia, Cytospora, Glomerella, Haplosporella and Ulocladium.

Investigation of numerous foreign seeds from the same latitude as Ottawa (about 45 N) yielded no additional records and a limited variety of very common saprophytic species were obtained.