In Québec, the genus Gymnosporangium (family Gymnosporangiaceae) counts 6 species of mushrooms. The stars? Mountain ash juniper rust, Cedar quince rust and Cedar-Hawthorn Rust, the most often observed. The richest region: Bas-Saint-Laurent, with 4 species. Every species has its own page: photos, its season, its habitat and the best places to see it near you.