Foamy bark canker

The foamy bark canker is a disease affecting oak trees in California caused by the fungus Geosmithia sp.

The bark beetles target oak trees and bore holes through the peridermal tissues, making tunnels within the phloem.

This disease is important because of its detrimental effects on oak trees and its ability to spread to several new Californian counties in just a couple of years.

Symptoms causing branch dieback and tree death also include a cinnamon-colored gum seeping from multiple beetle entry holes on the bole, followed by a prolific, cream-colored foamy liquid.

#41 and burrows into the host tree, depositing the fungus inside the phloem where the female beetle lays its eggs.

[citation needed] This disease has been found in the southern coastal regions of California where the climate is mild and constant year-round.

[10] Other cultural techniques of sanitation and overall health of the oak trees by keeping up with watering, fertilizer or mulch needs, and pruning may help.

[citation needed] Although the disease is caused by a relatively new symbiosis, it has already spread to a number of different counties, and is completely wiping out oak trees.

Oak trees are important for wildlife diversity and for the ecological services they provide like habitat, shelter and food.