White pine blister rust

white pine trunk with orange color fungus on it.

White pine blister rust is an invasive fungal disease introduced into North America in the early 1900s on infected planting stock from Europe. Since then it has become the most important disease of white pine. The disease requires alternate hosts in the genus Ribes (currants and gooseberries) to complete its life cycle. Trees of all ages can be infected, but younger trees are killed at a much higher rate than mature white pines.

Location

map showing the range of white pine that follows a diagonal line from northwest Minnesota (Roseau Co.) to the southeast corner (Fillmore and Houston cos.)White pine blister rust is found throughout the range of white pine in Minnesota.