I've got two Orange trees and two avocado trees in my backyard. One of the orange trees looks to be the victim of a disease and has sooty mold on it. From what I have read this is usually due to animals which excrete honeydew which allows for this to occur. To attack this at the source I need to get rid of the animal/insect issue. Has anyone had a good experience or have any recommendations on which pesticide chemicals to use. If need be, I can hold back on eating the fruit for a year to resolve this issue (if the pesticide is not safe for consumption) as I have already started to see certain branches die off due to this.
The pesticide I have tried is "Ortho Elementals Garden Insect Killer" in a spray bottle which has the active ingredients of "Pyrethrins (0.01%), Canola Oil (1%) and other (98.99%)". It seems to have worked to a certain degree but was expensive. If I can get a recommendation on the right chemical to use then I can buy it in greater bulk online after testing it out. In a perfect world I would like to have something I can universally spray on both orange trees and avocado plants.
If I am taking the wrong approach to this then please let me know. Thank you for taking the time to read this.