When the branches of your trees and shrubs are bare in winter, you have an opportunity to spot cankers that might be hidden by leaves in summer. A canker is an area of disease in the wood of a plant.

Alan Buckingham, author of Allotment Month By Month, advises in his book that gardeners should inspect their apple and pear trees for signs of canker and remove any infected wood immediately.

In susceptible trees and shrubs, the fungus may attack the smallest twigs and later spread to larger branches where they cause cankers. Symptoms: Discoloration and death of leaves on individual stems ...

Cytospora canker generally appears on the lower branches first and then progresses up the tree. Individual upper branches may show these symptoms as well (as you are seeing in your blue spruce).

these trees can very quickly develop limb dieback or cankers. In many cases, cankers become more obvious during these periods of stress because they were already present before the drought stress ...

This tree is infected with the fungal pathogen that causes Pine Ghost Canker, which can be fatal for trees. (Akif Eskalen, UC Davis) Fungal pathogens that cause die-back in grape, avocado, citrus, nut ...

Jillian Patrie | University of Minnesota Yard and Garden Extension ...

As infections move downward from twigs and blossoms, localized cankers form on the trunk and limbs. Branch cankers become sunken and darkened and eventually cracked and creviced. Wounds to ...

Two separate chestnut blight inoculations (controlled, replicated intentional infections with the blight fungus) confirm that Darling 54 trees have smaller cankers than their non-transgenic siblings.

Fungal pathogens that cause die-back in grape, avocado, citrus, nut and other crops has found a new host and is infecting conifer trees causing Pine Ghost Canker in urban forest areas of Southern ...