I suspect I may have greening. Although my trees (2) are only 4-5 yrs. young, I do have about 3 dozen oranges on one tree and none on the other; I think it might be dwarfed. The one with the fruit is a Navel tree. I tasted one orange and it's not bitter and is quite orange in color. They are not fully developed yet, but if I have greening, who do I contact? I am in Bradenton, FL and any help would be appreciated.
Greening (Citrus Tree, Orange)
Certified GKH Gardening Expert
Contacting your local extension service is a good idea. They may be able to check your trees, and they definitely will have information about citrus greening and other citrus diseases in your area.
It looks like this is your local extension service: