top of page

Blister Rust

Affects

Concern Type

White pine blister rust is a fungal disease that attacks all five-needle or white pines.

White Pine

Disease

About this Tree Concern

White pine blister rust is caused by a non-native fungus which was introduced to North America from Europe or Asia in the early 1900s. The fungus produces five different spore stages on white pines. It forms cankers on the trunks and branches of white pines, which may then ooze resin and produce orange or rust-colored pustules. The disease can kill white pines and has reduced their populations significantly here in Ontario.

Remediation

Unfortunately there is no effective chemical treatment available. Prevention and early management are key. If you notice yellowing and rusty red needles, discolored or cracked bark where clear to white sap is oozing, or yellow blisters in the spring that are releasing powdery orange spores, this might be a tree that is infected.


Treatment consists of pruning the infected limbs while being careful not to spread the spores. In particular if you have multiple white pines on your property, taking action immediately could prevent the spread of this fungus.

Do you suspect blister rust on your pine tree?

bottom of page