Lawn and Garden
Citrus is an iconic part of Florida life. Up and down residential streets in Florida, most homes boast a citrus tree, the fruit is so plentiful it spills over fences and onto the sidewalks. Because of Citrus Greening (Huanglongbing ;HLB) all of these trees are now in danger. The disease slowly weakens and kills all types of citrus trees, and since it can take years before the first symptoms appear, greening has ample time to spread. Infected trees die within about five years; there is no known cure.
The disease is transmitted by a small winged insect, the Asian citrus psyllid, and it can be disastrous for commercial citrus farmers as well your dooryard citrus.
What can the homeowner do to help the existing trees and future trees? According to Dr. Stephen Futch, from the University of Florida, protecting the existing homeowner trees is impossible. If greening is on your neighbor’s tree…it is more than likely on yours too.
At this point, if you do have HLB there are 2 options; you can immediately cut down the tree and burn it or you can still enjoy the fruit for several more years, and when the fruit becomes unable to eat, cut down the tree then burn it.
As for new trees, only buy citrus trees from reputable, licensed Florida nurseries. All new citrus trees being sold by licensed nurseries have been treated with insecticides. To prevent HLB, you will need to continue treatments on the citrus tree for its lifetime. Just understand you will at some point during the tree’s lifetime, not be able to apply enough to protect the tree.
According to Dr. Futch, systemic insecticides such as imidacloprid are an important part of psyllid control. Imidacloprid is a systemic insecticide that is taken up by the roots or other parts of the plant and then move internally through the plant tissues and kill insects feeding on those tissues.
Imidacloprid has been available to commercial growers for use on edible crops for over a decade. Homeowners, however, have not had any systemic insecticide available for insect control on fruits and vegetables until recently. A new product called Bayer Advanced Fruit, Citrus & Vegetable Insect Control is now available for the general public. It contains 0.235% imidacloprid. This product can only be applied to the soil.
The scientists from the University of Florida are working on an answer for Citrus Greening. Until a cure is found, making sure you have healthily citrus trees is all you can do right now.
If you think your citrus may have Citrus Greening (HBL) call either: Southern Gardens Diagnostic Laboratory-(863) 902-2249 or Florida Division of Plant Industry-(800) 282-5153 or UF Plant Diagnostic Center-(352) 392-1795.