The mycological collection holds over 350,000 fungal and fungal plant disease specimens which make it the largest fungarium of non lichenized fungi in Canada. The specimens are used as vouchers for scientific research, scientific names and living fungal cultures maintained in the Canadian Collection of Fungal Cultures (CCFC). Herbarium specimens document the existence of indigenous and invasive species (agents of disease: pathogens, toxigenic species, symbionts, saprophytes and other biodiversity components) in all Canadian provinces and territories, on different types of hosts, at different stages of their life cycles, and during different times of the year. The fungarium also holds many representatives of foreign disease-causing fungi which can be used for comparative purposes. Lichenized fungi (that is to say, those forming lichens) are generally excluded and by written agreement are housed in the lichen section (CANL) of the National Herbarium of Canada (CAN) at the Canadian Museum of Nature.