How do you get rid of canker from pear trees and buddleias?
Canker has been on pear tree for many years, but has spread to other shrubs in the garden.
Cankers are caused by fungal or bacterial infections. The best treatment is 1) optimal cultural practices to ensure that plants are healthy and able to ward off infection; 2) removal of diseased areas and rigorous disposal of fallen plant material. This article will tell you more: https://www.gardeningknowhow.com/ornamental/trees/tgen/cankers-on-trees.htm