Insect Infestation Help: Valencia Orange Tree

[joshwakefield]

All,

I'm in my 4th year of growing a Valencia Orange Tree.

For context I keep the tree potted (very large pot) and it spends the summers outdoors and then in a small green-house like corner window I have in the colder months.

When I moved it in this year I've noticed the soil around the base of the tree was crawling with these bugs. They almost look like tiny fleas or gnats to me. Seem to have wings and can fly (but mostly don't) but when in the dirt you can barely see them with the human eye.

I've been using Insecticidal Soap (Captain Jack's Insecticidal Super Soap) spray for the last 10-14 days. I feel like I'm not making dent. Literally every morning I wake up and get real close to the soil and there is a fresh batch of these guys crawling around. I spray them like 2-4 times a day whenever I seen movement. I've probably gone through 60% of my 32oz spray bottle.

Anyways I thought I would check if someone had other recommendations for how to mitigate this issue? What are these bugs? How do I get rid of them?

Sidenote: I'm not really noticing any adverse effects to the tree itself (which is good I guess) but am just generally concerned for the tree and my house.

Thanks,

Josh

 

[Chuck]

It sounds as if you have a fruit fly/fungus gnat infestation. You are probably killing the gnats you are spraying but they are coming back from eggs laid in the soil. Spraying will not work. You should use a soil drench but first you must understand why they are there in the first place. Simply put, you are keeping the soil to moist. Let the top 2 or 3 inches of soil become DRY. Not slightly damp but DRY as a bone. Here is how to make a drench. Use 2 oz of your Captain Jack's concentrate per gallon of water and saturate the top 2 or 3 inches. This will kill the larvae and eggs. If this doesn't work do the same thing with 1 part 3% hydrogen peroxide to 4 parts water and if that doesn't work use 2 oz Neem Oil per gallon of water, but I am sure the spinosad in the Captain Jack's will work great. I just now noticed that your Captain Jacks's is not a concentrate but a RTU. This will not work as a soil drench unless you just pour it out of the bottle.

 

[joshwakefield]

This is incredibly helpful. I picked up some Captain Jack's concentrate and made a 1 gallon soak as you suggested. Just applied it so we'll see if it does the trick. I tired to get things as BONE DRY as possible, went as long as I could before I thought the plant might be struggling without water. Will let you know if I see an improvement. Any reason to reapply a soak in X days or something just to be sure?

 

[Chuck]

This is incredibly helpful. I picked up some Captain Jack's concentrate and made a 1 gallon soak as you suggested. Just applied it so we'll see if it does the trick. I tired to get things as BONE DRY as possible, went as long as I could before I thought the plant might be struggling without water. Will let you know if I see an improvement. Any reason to reapply a soak in X days or something just to be sure?

Just remember that the roots are deep in the container, the major portion of them at least 1/2 way down, so even if the top 2 or 3 inches are bone dry there is still plenty of moisture down where the roots are. I would reapply the next time the plants need to be watered just to make sure. Fruit flys/ fungus gnats will not harm the tree. They are just a big nuisance so I would continue to carefully observe and spray when and if you see any.

 

[joshwakefield]

Ok so I must not be making this BONE DRY enough. I have done two soaks in the last 12 days. Killed LOTS of bugs, but I'm still seeing them in the soil. Any other thoughts. These bastards are tough.

 

[Chuck]

Ok so I must not be making this BONE DRY enough. I have done two soaks in the last 12 days. Killed LOTS of bugs, but I'm still seeing them in the soil. Any other thoughts. These bastards are tough.

What you are seeing are freshly hatched insects from eggs deep in the soil. If you continue to drench every time you water you will be able to eliminate them. You can also use a soil drench of Neem Oil which does a better job of killing eggs than spinosad but does not kill the insects as well. Or you can use a combination of the two.

 

[joshwakefield]

Neem Oil ordered, I will do both.

Just to be clear, there is no detrimental impact on the plant itself from either?

Thanks for all your help Chuck I really appreciate it.

 

[Chuck]

Neem Oil ordered, I will do both.

Just to be clear, there is no detrimental impact on the plant itself from either?

Thanks for all your help Chuck I really appreciate it.

Using Neem can be detrimental if you allow it to get on the foliage during a hot day with intense sunlight but, if used in the AM or late afternoon no need to worry

 

[joshwakefield]

Another thought. Just finished both Neem and Captain Jack's applications last week, I'm still seeing a lot of bugs. What if I complimented my drench with just wrapping the base of my tree (pot and all) in a trashbag and just cutting off air-flow/light to that area?

 

[joshwakefield]

Also, I'm starting to see (for the first time) where some of the leaves look like they are being eaten through (holes). Would these bugs be able to do that?

I'm going to add a few images of some of the bugs I captured on a sticky strip that might help with identification. As well as a view of the tree as well.

 

[Chuck]

Another thought. Just finished both Neem and Captain Jack's applications last week, I'm still seeing a lot of bugs. What if I complimented my drench with just wrapping the base of my tree (pot and all) in a trashbag and just cutting off air-flow/light to that area?

WILL NOT WORK. Just think of how much oxygen is in the soil. In the atmosphere around the plant and how small the insects are and how little oxygen they use. Those are fungus gnats. They lay eggs in the moist soil, hatch and start flying around. They eat dead and decomposing organic matter. They will not harm your tree. They are a nuisance, nothing else. Those holes are from something else. Either a chewing insect or a caterpillar. The Captain Jacks will work on both. Just keep on doing what you are doing. It will eventually kill them all. Remove that leaf in the last picture and look on the reverse side with a magnifying glass and see if there are any super tiny insects.

 

[joshwakefield]

Fair point on the oxygen should have caught that.

I can't imagine what is eating the leaves as this has been inside for well over 30 days....weird.

I looked on the underside of the leaf in the last pic and no tiny insects i could see (used zoom on camera and then a magnifying glass)

I have a couple leaves with that white looking residue, and on 2 others there is similar but brown. Should I remove these when I see them?

Thanks again for all your help I'll keep up drenching.

 

[Chuck]

Fair point on the oxygen should have caught that.

I can't imagine what is eating the leaves as this has been inside for well over 30 days....weird.

I looked on the underside of the leaf in the last pic and no tiny insects i could see (used zoom on camera and then a magnifying glass)

I have a couple leaves with that white looking residue, and on 2 others there is similar but brown. Should I remove these when I see them?

Thanks again for all your help I'll keep up drenching.

Have you sprayed the trees leaves with Neem? If so, is there a chance that the tree was in direct sunlight while the Neem was still wet on the leaves? The sunlight through the window and the oil in the Neem will act as a magnifyer causing leaf burn and the picture shows what could be leaf burn. And that white is not a residue, it is dead leaf tissue. The brown spots will probably turn white. What concerns me is the color change in the leaf, where it goes from a normal dark green to a yellowish-mottled green. This is indicative of citrus mites. I would remove all leaves with this coloration just to make sure that if it is citrus mite you can stay ahead of the problem. About the holes in the leaves as shown in picture 3, is the edges of the holes dried and brown or are they a greenish color. If dried and brown that is old damage and nothing to worry about.

 

[joshwakefield]

I have not sprayed any of the leaves with Neem, only the Capt. Jacks Insecticidal Super Soap (non-concentrate) where I saw bugs flying. All treatment outside of that has been in the soil.

I will remove leaves where I see the whitish/green mottling in case there are mites.

I'm including some other pictures of other discoloration I'm seeing (only 1-3 leaves total) and the holes closer up. To me they don't look like brown edge, just pure green.

 

[Chuck]

I have not sprayed any of the leaves with Neem, only the Capt. Jacks Insecticidal Super Soap (non-concentrate) where I saw bugs flying. All treatment outside of that has been in the soil.

I will remove leaves where I see the whitish/green mottling in case there are mites.

I'm including some other pictures of other discoloration I'm seeing (only 1-3 leaves total) and the holes closer up. To me they don't look like brown edge, just pure green.

View attachment 93448View attachment 93449View attachment 93450

In the first picture at the 9 o'clock position there appears to be a spider web with tiny white particles. It looks like it could be mites and the center vein of the leaf with the white looks like mite damage also. The hole at the 3 o'clock position is old damage. Picture #2 also appears to be old damage. In the last picture the dark brown color could be sooty mold from mites also. I would remove this leaf. I also notice tiny white spots in the background leaves. What is that? Take a very close look. Is there any type of damage or discoloration to the fruits on the tree?

 

[joshwakefield]

It isn't a spiderweb was just the lighting, I looked again and didn't see any insects on any side of the leaf. Should I remove the leaf in picture #1?

Removed the leaf in picture 3 and any like it (there were 3)

I've included some pics of the white spots in the background you reference as well as my current fruit load. The fruit looks great in my opinion. Valencia oranges take forever to ripen.

 

[Chuck]

It isn't a spiderweb was just the lighting, I looked again and didn't see any insects on any side of the leaf. Should I remove the leaf in picture #1?

Removed the leaf in picture 3 and any like it (there were 3)

I've included some pics of the white spots in the background you reference as well as my current fruit load. The fruit looks great in my opinion. Valencia oranges take forever to ripen.

View attachment 93452View attachment 93453View attachment 93454View attachment 93455

I would remove that leaf as well. Your fruit looks good as I see no evidence of mites on them. That last picture of the white spots is old damage and the offending insect was killed when you sprayed with spinosad. I still see white web-looking stuff on quite a few leaves, especially in the last picture. Here is what I would do if the plant were mine. I would spray with Neem on every inch of the plant. I would spray LATE LATE in the afternoon to ensure that the plant would not burn. Neem Oil is an insecticide, fungicide and a miticide but Neem Oil is limited by its shelf life. Once opened, a bottle of Neem will lose its effectiveness in about 6 weeks. It is still effective against eggs, however. I don't know for sure but I think you are in the early stages of a citrus mite infestation. It is much easier to take precautions now than it is to wait until the mites start their reproductive process.

 

[joshwakefield]

Thanks Chuck will do a neem spray tomorrow late afternoon and report back.

 

[joshwakefield]

Chuck,

Sorry I forgot to follow up but the small bug problem DID drop off and we had none from mid-november until now. Just today I saw some pop up which seemed odd in December to me. So I started thinking....what's different? And I realized I forgot to provide you with now what I realize is a critical piece to this puzzle. I had/have been using EcoScraps Citrus Fertilizer on the tree.

EcoScraps Citrus Fertilizer

I now realize that fertilizer is causing these bugs for sure. Because I had not added any (was instructed to only use once ever 1-2 months). since Early October (when initial problem started).

Is this expected with all fertilizers? Any suggestions on others I should use instead and/or do I even need to be fertilizing?

Thanks as always for all your help and advice.

Josh

 

[Chuck]

Chuck,

Sorry I forgot to follow up but the small bug problem DID drop off and we had none from mid-november until now. Just today I saw some pop up which seemed odd in December to me. So I started thinking....what's different? And I realized I forgot to provide you with now what I realize is a critical piece to this puzzle. I had/have been using EcoScraps Citrus Fertilizer on the tree.

EcoScraps Citrus Fertilizer

I now realize that fertilizer is causing these bugs for sure. Because I had not added any (was instructed to only use once ever 1-2 months). since Early October (when initial problem started).

Is this expected with all fertilizers? Any suggestions on others I should use instead and/or do I even need to be fertilizing?

Thanks as always for all your help and advice.

Josh

I looked at the ingredients label and there is nothing that the fertilizer is made from to cause insects to be attracted to the plant. Everything is basic organic materials. This is good fertilizer, a tad expensive, but good stuff. All citrus needs to be fertilized and this fertilizer is a slow release, fairly inclusive product.
Are these new insects the same as when you first posted. If so all you have to do is give the soil a good drench with Neem Oil to kill them and the eggs. It is also a good practice to lightly prophylactically spray about twice per month even if you don't see any insects. Fungus gnats breed in moist soil. If you adjust your watering schedule and let the top couple of inches dry out more you will not have these annoying bugs.