This fungus was introduced into North America on white pine seedlings from Europe in the 1890's.
Teliospores germinate to form basidia which produce basidiospores.
In the spring, 3-6 years after initial infection, aecial structures are formed. Spores produced on the undersides of infected Ribes leaves are wind blown to white pine needles during cool, wet periods from July to October. During the next twelve to eighteen months, the fungus grows within the needle, into the twig, and enters the branch. A canker, swollen resinous lesion, develops and continues to grow as long as the branch remains alive. If a canker girdles a branch, the movement of water and nutrients is blocked and the branch dies from that point outward.