Tar spot needle cast

• French disease name: Rouge du pin gris
• Pathogen name: Davisomycella ampla (J.J. Davis) Darker
• Kingdom: Fungi
• Phylum: Ascomycota
• Class: Leotiomycetes
• Order: Rhytismatales
• Family: Rhytismataceae
• Partial list of synonyms:
  • Hypodermella ampla (J.J. Davis) Darker
  • Lophodermium ampla (J.J. Davis) J.J. Davis

Distribution

Canada

Damage, symptoms and biology

Oval, black fruiting bodies form on straw-coloured portions of needles. These areas are often separated from green tissue by an orange-brown band.

Other information

The spores mature in late May and early June on needles infected the previous year. In humid weather, the fruiting bodies open and their spores are dispersed by wind and rain. Spores deposited on current-year needles are the source of new infections. Needles infected the previous year drop at that time. A serious infection can reduce growth.

Canadian Forest Service Publications

Tar spot needle cast

Information on host(s)

Main host(s)

Jack pine, shore pine

Secondary host(s)

Lodgepole pine

Photos

Fruiting bodies of Davisomycella ampla on lodgepole pine

Eric Allen

Tar spot needle cast, caused by Davisomycella ampla, on jack pine.

Fruiting bodies of the tar spot needle cast fungus, Davisomycella ampla, on jack pine needles early in the summer of their second year.