Cherry trees have showy pink blooms that can be destroyed by pests. Among the insects that attack cherry trees is the black cherry aphid. Aphids suck the sap from plant leaves and leave behind a honeydew secretion that promotes the growth of black mould. Monitor cherry trees year round for aphids, and treat them as soon as possible to ensure a healthy tree.
Inspect leaves to ensure that aphids are the problem. Black cherry aphids are characterised by a shiny black body and are 1/8 inch in length; they typically populate the underside of leaves. The damage caused by aphids includes the curling and twisting of leaves.
Release natural predators to a tree during the dormant period to reduce the aphid population without having to use chemicals. Natural predators include lady birds and lacewings, and can be purchased through garden centres and online retailers. Release natural predators on the tree at the points where aphid populations are the highest.
Use insecticides shortly after petal fall if natural predators are not able to control the population. Insecticides approved for black cherry aphids include imidacloprid and thiamethoxam. Dilute the insecticides to approximately 59.1mls. per 100 gallons of water, or as directed.
Do not enter an area where insecticide has been applied for at least 12 hours.