Citrus Leafminers and Organic Pest Control

June 21, 2022 Bill Hageman

Citrus Leafminers are a common pest in California

Citrus leafminers (Phyllocnistis citrella) are a type of insect that feeds on the leaves of citrus trees. They are small, slender insects that are difficult to spot. These pests feed on the leaves of the tree, leaving behind telltale serpentine trails. The larvae tunnel through the leaf tissue, causing extensive injury. This damage can lead to early defoliation and reduced fruit production, as well as Canker disease and death of the tree.

Leafminers are most commonly found on Citrus sinensis (or sweet oranges), Citrus limon (lemons), and Citrus aurantium (oranges). However, they have also been known to infest other citrus species such as grapefruits and limes. Citrus leafminers can be difficult to control once they become established, so it is important to take action as soon as possible.

In this blog post, we will discuss organic methods of controlling citrus leaf miners. We will also provide instructions on how to set up insect traps and use lures to attract and capture these pesky insects!

Sticky Traps

One method is to use sticky traps. These traps are placed on the leaves of the tree and help to capture the leaf miners as they feed. The traps capture the adult male moth disrupting the mating process. The traps are used in combination with lures which last approximately 90 days. You will need to check the traps regularly; depending on capture they will need to be replaced during this timeframe.

Lures

Another method is to use lures which can be purchased independently or with the traps. Citrus leaf miners are attracted to certain pheromone scents, so you can use this to your advantage! There are various lures available that emit pheromones to attract the insects to be trapped or killed.

Common Organic Insecticide Sprays

General purpose insect sprays such as Monterey Garden Insect Spray Ready To Use (RTU) or Neem Oil are used commonly across a broad spectrum of insects. These must be applied regularly to consistently disrupt the insects' mating patterns.

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We offer a number of natural pest control and organic options for sale.

Consult with a pest control expert to develop a plan that's right for you and always read the manufacturer's instructions for additional detail.

FAQs About Citrus Leafminers in California

Are citrus leafminers common in California?

Yes. Citrus leafminers (Phyllocnistis citrella) are established in many citrus-growing areas of California, particularly in Southern California. According to University of California IPM, they are most problematic in backyard citrus and young trees, especially during periods of active new growth.

What plants do citrus leafminers attack?

Citrus leafminers primarily infest citrus species such as sweet orange (Citrus sinensis), lemon (Citrus limon), lime, grapefruit, and other citrus varieties. They prefer tender new leaf flush and are less damaging to mature, hardened leaves.

Do citrus leafminers kill trees?

Citrus leafminers rarely kill established trees. However, heavy infestations can stunt young trees and reduce vigor. Leaf damage can also increase susceptibility to diseases such as citrus canker, particularly in regions where the disease is present.

Do sticky traps and pheromone lures help control citrus leafminers?

Sticky traps combined with pheromone lures are primarily used for monitoring adult moth activity. While they can capture male moths and help track population levels, university extension sources note that traps alone typically do not eliminate infestations. They are most useful for determining when treatment may be needed.

What organic methods are effective against citrus leafminers?

Organic control options include encouraging natural enemies such as parasitic wasps, applying products containing spinosad to new leaf flush when larvae are young, and using horticultural oils to deter egg laying. Treatments are most effective when timed to coincide with new growth, as larvae are protected once fully inside leaf tissue.

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1 comment

Tried the traps with pheromone lures and was shocked: in less than 24 hours, hundreds of leafminers had been trapped, without a single “innocent bystander” (the downside of plain sticky traps is that any flying insect, including bees, will get stuck and die). The design of the traps is such that other insects cannot accidentally get trapped, while the lure seems to be irresistible to the citrus leafminers. I will definitely be putting them out in the spring, when the miners first start to become active, in the hopes of preventing as much damage as possible.