Septoria musiva on Hybrid Poplar in Southern Ontario. L. J. Spielman, Postdoctoral Fellow, Faculty of Forestry, University of Toronto, Ontario, Canada M5S 1A1. M. Hubbes, Professor, and D. Lin, Research Assistant, Faculty of Forestry, University of Toronto, Ontario, Canada M5S 1A1. Plant Dis. 70:968-971. Accepted for publication 26 April 1986. Copyright 1986 The American Phytopathological Society. DOI: 10.1094/PD-70-968.

Septoria canker, caused by Septoria musiva (teleomorph: Mycosphaerella populorum), was found in plantations of hybrid poplar at three locations in southern Ontario in 1983 and 1984. This disease had not been found in surveys between 1978 and 1982. Isolates from Ontario and the United States were similar in cultural morphology, temperature requirements, and virulence in artificial inoculation tests.