Black Knot
What is Black Knot?
Black Knot is caused by the fungus Apiosporina morbosa, it is a very common disease of plants in the genus Prunus. A survey in Alberta revealed a significant and widespread distribution of Black Knot found in commercial, municipal, private and natural plantings. This disease reduces the aesthetic value of affected specimens, as infections spread rapidly; high levels may result in the eventual death of the plant.
The plants that are effected by Black Knot can be found at the following link - https://www.alberta.ca/black-knot.aspx
Black Knot will affect other trees in the area if it is not dealt with
When do you get rid of Black Knot?
Black Knot should be removed when it is first spotted, the best time of the year to remove it is early spring or late fall when the plant is dormant. Winter will also work but who wants to prune trees in the Alberta cold!?
Removing the fungus does not guarantee that it won't come back but it is a good preventive maintenance with keeping your tree healthy.
How do you remove Black Knot?
Black knot needs to be removed from the tree with care if possible. If the fungus breaks open the spores will then travel in the wind to neighboring trees and infect them. You should cut a minimum of 6 inches off from the black knot. Tree branches that have been infected for a while will look like it has been eaten by the fungus (See the picture) once that happens the entire branch needs to be removed from the tree.
After the pruning is complete, then you MUST sterilize your equipment to avoid spreading the fungus to other trees.
The safest way to remove Black Knot is to give us a call and let us deal with the hassle of it and to make sure it does not spread to other trees.