Black Knot Fungus: Treatment & Prevention | Jung Seed's Gardening Blog

Black Knot is a common fungal disease that affects different species of Prunus, such as cherry, peach, and plums. This type of fungus spreads mainly by spores carried on the wind in spring to infect new trees, however, the galls or knotty growths are not noticeable until late summer or even fall, after trees have lost their leaves. Now is the time to develop a prevention plan. What Is Black Knot Fungus Apiosporina morbosa is the responsible pathogen for the disease called Black Knot, which creates symptoms of black, knotty growths or galls that form on twigs, limbs, and sometimes trunks of susceptible trees. In areas where native, wild plums are common, this fungus is typically more common, so be aware of your local surroundings, when choosing what tree types to plant. If there are a lot of wild plums, planting apples may be a better option. Trees Affected By Black Knot Black Knot is common on Prunus spp., including ornamental and wild plums, cherries, peaches, and other stone fruits l...