How can I treat Sooty Canker on a grapefruit tree?

A good solution of bleach to water is one part bleach to nine parts water. Control of the disease is feasible when an infection is confined to tree limbs. It becomes virtually impossible to control the disease after the tree trunk becomes infected. If small infected branches can be identified when the tree is in leaf, they should be removed. Large limbs 1 1⁄2 inches or more in diameter should be removed when infected trees are dormant. Limbs partially affected with the disease should be cut back below the site of the infection. The cut area should be treated with a solution of one part household bleach to nine parts water. Pruning equipment should also be treated with the bleach solution between each pruning cut to preventive measure. Infected prunings should be quickly discarded. Trees should be fertilized and deep watered on a regular schedule. Recommended Publications: Sooty Canker Diseases of Urban Plants