Today’s topic is a little more out there than roaches and ants. But, it’s a huge problem for the sunshine state. The topic of this article is the Florida Citrus Leafminer. We’ll cover what it is, what it does, and what you can do to help control it or get rid of it altogether.
So if you’ve seen the leaves of your citrus tree curl up and die, and squiggly lines appearing in them, you probably want to read on.
Florida Citrus LeafMiner: What is this Bug?
The citrus leafminer is a small moth from Asia. Their larvae dig “mines” in citrus leaves as they grow and eat. This insect wasn’t introduced into the United States until the 1990s, and has spread into many other states. The citrus leaf miner also nests in Mexico, the Caribbean islands, and Central America. Everywhere they go they cause damage to citrus trees, so if you have anything from a single orange tree to an orchard, you should look out for this pest.
Leafminer damage to foliage can stunt the growth of young trees. They can also make adults more susceptible to citrus canker where the pathogen is present. Mature trees can tolerate the damage overall, but heavy infestations of the Florida citrus leafminer will cause a reduction in production.
The adult leafminer is a small, silver moth was a wingspan of about four millimeters. Their wings have several black and tan spots, and a small black dot on the tips of their wings. The adults are only seen rarely, and are active early in the morning and late in the evening. The females lay eggs singly on the underside of new leaves. When this egg hatches, the larvae enter and begin consuming the leaf from inside. The adults-only live a few days. The life cycle can take from 13 to 52 days depending on conditions. In Florida, the life cycle is about 21 days, and populations peak in summer and early fall. In southern Georgia and northern Florida, the life cycle is interrupted by winter. The leaf damage from the larvae is usually the first indication of their presence.
Baited traps can be deployed beforehand to access the overall presence of the moth in your trees as well.
Controlling the Florida Citrus Leafminer without Insecticide
Now, later in the article, I will cover one way that you may control this insect with chemicals. But, I don’t believe in chemical pesticides because of the long since proven facts that it’s a danger to your health and the health of your family, so we’ll cover the better ways first. To start with, mating disruption can be a key in dealing with this flying pest.
There is a system based on mating disruption for citrus leafminer control. The system works by emitting high quantities of sexual pheromones that disrupt mating and the males’ ability to find females. Monitoring leafminers is important to develop a program of mating disruption. A product called “SPLAT-CLM” that releases a high quantity of pheromones is commercially available and can be applied on citrus. A reduction in mating causes a reduction of fertilized eggs and results in fewer larvae.
Attract-And-Kill
The name is a pretty dead give away of what exactly is going on with this method of pest control. This combines a potent attractant and a low yield quantity of chemicals and minimizes the risk of drift.
Pheromones are ideal types of attractants for such formulations. Pheromones are species-specific and will not affect non-target organisms; are highly potent, attracting male moths from hundreds of yards away; and they exploit a critical behavior for the survival of the species — mate finding prior to reproduction.
The advantages of attract-and-kill are that there are no insecticide residues left on the fruit, no effects on non-target organisms or beneficial, no re-entry or preharvest intervals, and no concerns about the drift of the applied material. The species-specific nature of the attractant can be viewed as both an advantage (no harm to biological control agents or bees) or disadvantage (no effect on other pest species such as psyllids or mealybugs).
What about for the home?
Now, most people that read this don’t have giant orchards. That means you’ll need less of anything to get rid of these. Whether it’s because you’re just trying to protect one to up to five or six citrus trees on your property. There are a few ways you can go down this path.
Use products containing imidacloprid, such as Bayer Advanced Fruit, Citrus, and Vegetable Insect Control, as a drench or foliar spray. Foliar sprays of natural materials such as azadirachin (Safer BioNEEM) or spinosad (Green Light Insect Spray) have some efficacy but will need to be repeated. Applying horticultural oils 10 to 14days apart as soon as new shoots begin to develop may help reduce leafminers. Stop use when the leaves harden off. Do not apply when temperatures rise to above 85 degrees Fahrenheit to prevent phytotoxicity. None of these materials will harm beneficial insects. These are all viable home controls for the Florida citrus leafminer.
Chemical Control
Now I’m going to go ahead and put this here, but using these methods WILL be more effective in killing the pest. But that also means that there’s a risk to yourself, and you will almost certainly kill any beneficial insects on the plant. One way is to use Foliar sprays on your trees. Products such asmethoxyfenozide (Intrepid 2F), spinetoram (Delegate), diflubenzuron (Micromite), or abamectin (Agri-Mek). These work best if mixed with petroleum oils. Foliar sprays of imidacloprid are successful when used before or after bloom. Avoid applications of malathion, pyrethroids, and carbaryl as they will kill beneficial insects that can result in a flare-up of mites, scales, aphids, and whiteflies. Avoid spraying neonicotinoids (imidacloprid) if already applied as a soil drench.
Florida Citrus Leafminer: Other options
As I said above, I’m a big believer in not using chemicals to kill pests. So if you’re having trouble with this insect, I have a suggestion. Look into hiring a dedicated, natural pest control specialist. Leave it to the pros, and make sure those pros are looking out for you as well.
