Although the avocado is largely known for its delicious taste and enormous health benefits, this nutritious fruit is not the easiest crop to grow. In fact, after planting seed, you might not reap your first harvest for several years. The last thing you need is for avocado tree pests or avocado tree diseases to interfere with this already lengthy process.
Whether you own commercial avocado orchards or whether you’re learning how to grow a few backyard avocado trees, here are six of the most common avocado tree pests you should know about.
There are a variety of borers—such as Polyphagous Shothole Borers and the Kuroshio Shothole Borers—that plague avocado trees.
This small, beetle-like pest of avocado trees will burrow, create tunnel systems for their fellow borers, lay eggs, and multiply—weakening tree trunks and branches in the process.
How to Spot a Borer Infestation
Borer infestations are often difficult to spot, as these insects don’t tend to linger in plain sight for very long.
Rather, these elusive pests will dig holes and hide beneath the surface of your avocado trees. The most common signs of a borer infestation are visible holes and weakened branches.
How to Get Rid of Borers
Borers tend to gravitate towards stressed trees, so keeping your avocado trees healthy and properly nourished can help prevent a borer infestation.
To eliminate a borer infestation that has already occurred, you will need to promptly cut down any and all infested branches and make sure that you remove them from the area.
Long before they bloom into gorgeous butterflies, caterpillars are known for targeting all kinds of tree species— including avocado trees.
Because caterpillars don’t need an abundance of time to inflict damage on your avocado trees, it’s critical that you keep your eyes peeled for potential caterpillar infestations.
How to Spot a Caterpillar Infestation
Caterpillar infestations are fairly easy to spot, as far as avocado tree pests go, since these critters leave visible trails of destruction in their wake.
Because most caterpillars like to munch on leaves, your avocado tree leaves are likely to be littered with holes and damaged edges. What’s more, there are certain types of caterpillars—such as Western Avocado Leafrollers—that like to wrap themselves in rolled-up leaves and bind them with silk for added protection.
How to Get Rid of Caterpillars
There are a handful of ways to eliminate caterpillar infestations—including several natural remedies that are safe for humans, animals, and the environment.
Try spraying down your avocado tree leaves with Bacillus thuringiensis, a soil-dwelling bacterium that is harmless to humans but toxic to insects. Just be sure to also spray inside any leaf-and-silk cocoons where caterpillars may be hiding!
3. Lace Bugs
Adult avocado lace bugs are tiny, winged insects that measure roughly two millimeters long and are known for their net-like patterns. Avocado lace bug nymphs are similar in appearance to adult lace bugs but lack wings. There are well over 2,000 lace bug species worldwide that feed on a variety of plants and they are included among avocado tree pests.
Although quite small, these natural enemies can deliver irritating bites. It’s best to steer clear of them and treat your avocado trees frequently in order to keep these pests away.
How to Spot a Lace Bug Infestation
Because of the lace bug’s miniature size and lacey wings, it’s easy for this invasive pest to blend in with its environment and go undetected. However, there are a couple of ways to identify a lace bug infestation.
Keep an eye out for dry, yellow, or black spots that appear on the undersides of leaves. These spots eventually cause damaged leaves to die and fall from your infected trees, so you may also notice a greater number of dead leaves when lace bugs are on the move.
How to Get Rid of Lace Bugs
When looking to treat your avocado trees or control of avocado lace bugs, it’s recommended that you spray your tree’s leaves with pesticides such as horticultural oils or pyrethrin.
Mites are tick-like insects that prey on a variety of crops. It’s estimated that there are between three and five million species of mites worldwide—including multiple pest species that are avocado tree pests.
Because the majority of these critters are brown mites, they are able to blend in with leaves that are either dead or in the process of turning dark brown.
How to Spot a Mite Infestation
Similar to lace bugs, mites feed on avocado trees in a way that leaves trails of small black and yellow spots.
There are certain species of mites—such as spider mites—that will even spin webs as they feed on your avocado trees. Look for these miniature spots and webs when inspecting your avocado trees for infestations.
How to Get Rid of Mites
When treating your avocado trees for mites, it’s important that you avoid all insecticides.
While these solutions may be effective when treating other infestations, they can have an adverse effect on mites. Rather than eliminating the mites, it may cause a spike in mite populations. Instead, treat your avocado tree leaves with horticultural oils.
While most avocado tree pests feed on the trees and their green leaves, thrips don’t tend to inflict the same kind of damage.
Rather, predatory thrips are known to affect the avocado itself—often leaving it scarred, turning the avocado brown, stunting the growth of your crop, and impacting the quality of the avocado fruit.
How to Spot a Thrip Infestation
Because avocado thrips affect the fruit, the reality is that you may not always be able to identify these insect infestations until an avocado fruit harvest arrives.
While you may be able to occasionally spot them feeding on the underside of leaves, you’re more likely to notice trails of brown scars and scabs on your avocado fruit. The fruit may even appear smaller in size, or you may see lighter crop yields than expected.
How to Get Rid of Thrips
Like lace bugs, avocado thrips largely respond to horticultural oils and pyrethrin. To prevent damage to avocados, however, it’s even more important that you protect your avocado fruit in advance.
You can help prevent a thrip infestation by keeping your tree healthy and strong with diligent fertilization and careful pruning—long before saplings develop into mature trees.
6. Garden Pests
Finally, there are all kinds of generalist predators—such as ants, grasshoppers, snails, and even parasitic wasps—that may also impact the overall health and growth of your avocado trees.
These critters will feed on all components of your avocado trees, from bark and branches to green leaves and fruit.
How to Spot a Garden Pest Infestation
Because the common pest can attack avocado trees in a handful of ways, the best way to spot an infestation is to keep a watchful eye on all areas of your avocado trees.
While grasshoppers might be found feeding on leaves of avocado trees, creating trails of brown spots, and causing general leaf discoloration, a group of garden snails might be scattered across your tree bark.
How to Get Rid of Garden Pests
Of course, due to the variety of garden pests that exist, there is no one-size-fits-all solution to eliminating these bugs.
To prevent ants from destroying your avocado trees, lay out insecticide or insecticidal soap during the winter. To stop grasshoppers from attacking your avocado leaves, apply insecticide to the areas surrounding your avocado trees. To combat snails, remove any moss or weeds surrounding your trees. Then, place copper bands around the tree trunks.
Safeguard Your Avocado Trees From Harmful Pests
As you can see, there are a variety of natural predators that may threaten your crops at any moment. Particularly after all of your hard work, an avocado tree pest infestation can be incredibly discouraging.
Avoid destruction to your trees and frustrating crop setbacks by keeping an eye out for these harmful pests. Once you spot a potential infestation, be sure to take swift action!
Have a tip about avocado tree pests you’d like to share? Leave it in the comments section below! And to read more about avocados, click here for our other avocado-related blog posts.