Like any other tree, there are countless pests and diseases attacking fig trees. It would be impossible to mention every single one, especially considering how many insect species there are worldwide.
I want to share my experience, and the experience of people I know well, about dealing with many different kinds of pests attacking fig trees and their fruit.
I’ve written a whole article on the common animals that attack fig trees and how to deal with them: How To Protect Fig Tree From Birds, Squirrels, and Deer.
Nematodes
The nematode is a parasitic eelworm that is tiny. It works on the roots of various crops, cotton, cereals, ornamental, orchard, and forest trees, with the soft, porous roots of figs providing great feeding. It can go down eight or ten inches in sandy soil, but four inches is the usual limit in heavy loams.
Two species commonly found in fig trees are Root Knot Nematodes, Dagger Nematodes, and a bit less common, Lesion Nematodes.
Ring Nematodes, and other less common types, are rarely damaging fig trees.
What Are the Symptoms of Nematodes in Fig Trees?
Root enlargements are frequently the first sign of its presence and are commonly mistaken for nodules on legumes. They are often so uniform in size and spacing that they resemble beads strung on strings; nonetheless, a single swelling can grow to reach six inches in diameter.
Nematodes, interfering with the flow of sap, the tree’s circulatory life fluid, cause harm. When the cellular fiber system becomes infested, its continuity is lost, and roots grow at infestation sites in unsuccessful attempts to produce enough cells for proper circulation.
The damage progression is slower in dry areas. Eventually, it leads to the whole tree slowly dying. It looks like it isn’t getting fertilized or lacking water.
How Do You Get Rid of Nematodes in a Fig Tree?
I’ve tried several experiments to get rid of, or at least control, Nematodes.
I’ve found that no treatment is effective in getting rid of them while preserving the tree. Nematodes are embedded so deeply in crucial areas of the roots system that getting rid of them requires toxic chemicals which irreversibly damage the tree.
If a tree is very young, cutting infected roots and replanting the tree somewhere else can work. However, it isn’t easy to regrow roots, even in young trees. Also, there is a risk of contaminating other areas because I found that Nematodes sometimes live in roots that seem healthy as well. They appear again once the roots grow.
However, I’ve found ways to control damage progression and even prevent them from infesting roots.
I’ve had a lot of success in controlling the nematode population with lime, unleashed ashes, and tobacco dust. These can even prevent nematodes if the soil is treated with them before a fig tree is planted.
A recommended prevention measure is cultivating the soil before planting. This is what I did with the soil additives mentioned above.
Since nematodes are mostly infecting shallow roots, cutting shallow roots and forcing a fig tree to grow deep roots is actually the most effective prevention method I’ve had. It would be best if you did it while the tree is younger because in later stages of the fig tree’s life, cutting shallow roots will likely kill the tree. A fig tree might even keep regrowing shallow roots out of stubbornness.
Fig Borer
This flat-headed bug is about one and a third inches long, light brown with white stripes on both sides of the body and down the back, wings, two long antennas, a flesh-colored mouth, and six legs.
Even though fig borer is the most common, I’ve seen many other species of beetles infecting fig trees.
What Are the Symptoms of Fig Borers in Trees?
Its horny mandibles can pierce living bark, although it rarely attacks a healthy, vigorous tree. The insect selects those who are stunted or frozen, and the beetle hastens their demise. Sometimes, even a healthy but dormant tree can be a good host for them.
I rely on knocking on wood most of the time. There will be a much louder sound on the spot where fig borer larvae are present. Other than that, and the fact that the part of a fig tree is dying, there is rarely any other sign.
How Do You Get Rid of Fig Borers in Trees?
Affected branches should be trimmed, and pests should be pulled out with a knife or destroyed by pouring a lethal substance into their holes if discovered in time. There are numerous pesticide solutions available on the market from which to choose to eliminate them.
Most people say fig borers are unaffected by common pesticides, but I find larvae and dump malathion pesticide in their hole. It usually destroys that branch, but it would die anyway. If they are in the base tree trunk, then I cut the part away two days later. That way, if any larvae remain, they are likely poisoned and won’t survive.
Adult beetles are resistant to 99% of pesticides. Therefore, prevention methods don’t work as well as with some other insect types unless you want to use pesticides all the time. I’m not a big fan of pesticides, so I won’t recommend them unless absolutely necessary.
It’s important to protect all the cut parts so that borers can’t dig and lay new eggs. I always use surgical gauze to protect cut tree limbs because it breathes no matter how many layers you apply. 3-4 are enough to protect from insects.
The same methods work on all beetles, with a slight difference with some chemicals being more poisonous against certain species.
Carpenter Worm
A carpenter worm is a wood borer that lays large larvae. Larvae with a size of 2 inches (5 cm) can tear through the fig’s sapwood in a short period of time. Although it’s not as common in fig trees as other insects, it likes to infest figs as much as any other tree.
The bad thing is that carpenter worm larvae take 2-4 years to grow fully. By that time, the whole tree is ruined.
What Are the Symptoms of Carpenter Worms in Trees?
I look for black sap patches on tree trunks, significant amounts of frass and sawdust discharged from the trunk, or damaged bark while looking for carpenter worm. In earlier infestations, pupal cases may protrude roughly two-thirds of the way through the tree bark.
A method of knocking on wood worked for me too. By knocking around, you can hear which parts are hollow beneath the bark. If I find one, I remove a piece of bark and check underneath. If a carpenter worm is present, you will see dark, dry sapwood and one or more holes. Holes can vary in size, so it’s hard to know that it is the carpenter worm.
Additionally, you can see gray moths on the tree. These are adult carpenter worms, most likely laying eggs.
How Do You Get Rid of Carpenter Worms in Trees?
I’d remove the branch with the most damage, then gently cut into it. I would photograph the tunnels just in case I don’t find the pest since it’s difficult to identify which pest made the tunnels unless you find them. Each bug takes on a unique form, twisting and digging in various ways. Often, just looking at the tunnels is enough for an expert to identify the pest.
Once you’ve identified the carpenter worm, you can proceed with the extermination and prevention methods.
Some experts recommend spraying and injecting pesticides, but I’ve heard that they didn’t work from several people.
Instead, I used Steinernema feltiae, a species of beneficial nematodes. They are proven to prevent and even exterminate carpenter worms. There are studies published on the topic, and beneficial nematodes are sold for this exact purpose. If you decide to go with this option, make sure to get the exact species I mentioned because there are others for different purposes.
How To Apply Beneficial Nematodes to a Fig Tree?
I apply beneficial nematodes using a squeeze bottle, mixing 1 million nematodes with distilled water. I try to inject the water into the holes which carpenter worms made. It’s way more effective than spraying the bark because nematodes die on dry open surfaces.
To achieve maximum effectiveness, it’s best to inject them in the evenings during the growing season. That way, the wood is moist, and nematodes are shielded from the sun in the evenings. I find it best to plug the holes afterward. Anything to minimize air flowing inside is good enough.
Several applications, one week apart, of this method can result in 100% efficiency.
Bear in mind; carpenter worms cause enough damage to the tree that sometimes it is unable to recover. Whatever species is tunneling, when the tree’s bark starts to fall off, it’s time to consider cutting it down. It is a danger. Standing deadwood, ready to fall over and injure you or others, or damage surrounding buildings, cars, or other property.
Spider Mites
A fig tree can be infected by a Pacific spider mite, a two-spotted spider mite, and a red spider mite. Both have black specks on a yellowish-green background.
What Are the Symptoms of Spider Mites on Fig Trees?
They eat the fig leaves’ undersides, causing them to darken and fall off. Luckily, you can notice them way sooner than leaves start to go brown. They rarely produce amounts of web big enough to notice, but turning a leaf here and there is always a good thing. You will find them underneath, especially if there was no rain for some time.
Occasional rain, or spraying leaves with water, proved an effective prevention method against spider mites for me.
How Do You Get Rid of Spider Mites on Fig Trees?
Spider mites are not nearly as tough to eradicate as some other parasites. However, they are frequently resistant to standard pesticides. To combat spider mites, you need a miticide like Forbid 4F.
I prefer to try other methods first because after using miticide like Forbid 4F, it’s not recommended to eat fruit from that tree for the whole year.
Other methods I’ve successfully used include dish soap mixed with water. I would spray mites every two days with it, and it would kill them. It’s slower than using miticide but much safer for the tree and you. Once spider mites are eradicated, wash the tree with clean water because soap can reduce the leaf’s ability to hold water in its cells.
If the fruit is already ripening, I avoid soap. I keep spraying all the leaves with water every day because they don’t like excessive humidity. It won’t eradicate them, only diminish their population, which is enough until the fruit season passes.
You can eat the fruit from spider mite infected trees without any worry. They don’t infest the fruit, only leaves.
I tried predator mites as well. Specifically, Phytoseiulus species and had tremendous success in eliminating a greenhouse infestation. However, the temperature must be above 20°C, and they are pricey!
Earwigs
Earwigs are common fruit tree inhabitants. They mostly eat the fruit. Even though they are beneficiary predators, I don’t particularly appreciate having them on my fig tree. They love to crawl inside figs. That’s one of the reasons why I open each fig before eating it.
How to Spot Earwigs on Fig Trees?
My best bet is looking for cuts in figs. I often find some of the figs cut on the side. I’m guessing they cut through there because the hole on the bottom of the fig was sticky from the leaking ooze.
Finding them around the tree often is also a bad sign. If earwigs are on the ground, they will be on the tree as well.
How to Get Rid of Earwigs on Fig Trees?
There is no effective way of getting rid of earwigs that are already on the tree. Even if you spray them with something, they will crawl inside figs to die, which I want to avoid. Having pesticide-infected dead earwigs in my fig fruit is the last thing I want.
Luckily, earwigs lay eggs on the ground and have to climb back up. Something sticky on the tree trunk can prevent them from infesting the tree quite effectively. Even though some sub-species are decent at flying, they still prefer to climb their way up.
I put some horticultural glue on the bark before the growing season starts. The last one I used was Tree Tanglefoot Insect Barrier from Amazon, and it worked well. Wrap any waterproof tape around the bark and add this glue on top of it. Any insect crawling up or down the tree will get stuck on it.
Scales
Scales are similar to spider mites, except they are much harder to get rid of because they produce a barrier they hide beneath. In addition to that, they attach themselves to the leaves and are difficult to remove physically.
How to Spot Scales on Fig Trees?
Same as spider mites, they cause leaves to darken and fall off. You can see them underneath leaves and even on stems.
Again, like spider mites, they don’t like leaves soaked in water, so rain and water spraying leaves is a good prevention method.
How to Get Rid of Scales on Fig Trees?
Scales are spreading from tree to tree way more aggressively than spider mites. When you combine that with the increased difficulty of eradicating them, sometimes it’s best to remove all the infected leaves and then apply prevention and treatment methods.
I found that horticultural oil is the most effective non-poison solution against them. Although, it isn’t as effective against fully grown scales. They require some additional measures.
The simplest solution is to scrape them off with a butter knife or any knife that isn’t particularly sharp. You don’t want to damage the leaf more than necessary. Applying horticultural oil afterward will eradicate any tiny scales left.
Navel Orangeworms
Navel orangeworms are famous for infecting nuts in California, but they are infecting figs as well. Navel orangeworm moths are attracted to figs, especially overly ripe ones.
They lay eggs inside fig fruit, and soon worms hatch. They start eating the fruit from the inside and make a mess of it. I haven’t had a problem with them yet because I pick figs several days before they are fully ripe. I’m guessing they don’t infect them at that point.
I’ve tried searching for solutions, but I found conflicting information and experts claiming there is no effective pesticide. The best solution seems to be prevention by removing all fruit from the tree and the ground on time.