Leaf blisters, soot and white powder


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I've got a Lemon Swirl in front of my house here in San Diego. Last year the leaves started to show blisters. After a while there was some white powder on the leaves and some black soot. Looking closer at the blister I see that on the backside of the leaves, insides the blister, there's a tiny round insect. Pushing them out of the blister I clearly see them moving around.

Now my Lemon Swirl is starting to drop all the leaves and looks kind of sad.

My research points me in the direction of Whiteflies, Aphids, Scales or Mealybugs. Thinking that the tiny bugs might a stage in these life of these bugs. But I really don't see any other bugs or stages.

I've been trying to use Neem oil, Pyrethrins + Canola Oil (Take Down Garden Spray) , Malathion and Imidacloprid (Bondie Soil Drench) with no apparent results

Would appreciate some expert help on identifying these unwelcome bugs and a suggested treatment.


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I've got a Lemon Swirl in front of my house here in San Diego. Last year the leaves started to show blisters. After a while there was some white powder on the leaves and some black soot. Looking closer at the blister I see that on the backside of the leaves, insides the blister, there's a tiny round insect. Pushing them out of the blister I clearly see them moving around.

Now my Lemon Swirl is starting to drop all the leaves and looks kind of sad.

My research points me in the direction of Whiteflies, Aphids, Scales or Mealybugs. Thinking that the tiny bugs might a stage in these life of these bugs. But I really don't see any other bugs or stages.

I've been trying to use Neem oil, Pyrethrins + Canola Oil (Take Down Garden Spray) , Malathion and Imidacloprid (Bondie Soil Drench) with no apparent results

Would appreciate some expert help on identifying these unwelcome bugs and a suggested treatment.


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I don't know much about galls except to know them when I see them. Those growths on your plants leaves are called galls. They are caused by certain insects, usually mites or aphids and there isn't a treatment as far as I know.
 
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So I read about a lot of plants called a lemon swirl and I do not know which lemon swirl you have by eye. I was trying to find the plant family. I was also reading with some interest on how nematodes are also members of the galling insect clan. Most of these are controlled by taking advantage of their transitional life phases. It would probably be useful to study nematode control protocol in your area, as temperature and moisture seasonality both play a huge role in the timing of effective control. Once they have burrowed in I think it is too late. I have had issues with the southern root knot nematode but controlled it by starting in the fall as the weather cooled and the numbers died back. After that it is basically laying chemical traps. One trap might be silicone spray, another like this thyme oil product I used to purify my garden. Impact their sense of smell, impact the taste or in the case of gallers then the ability to touch the cells of the leave without going through a waxy or silicone layer they cannot deal with. Its a hella thing they can do. But in the end, penetrating the leaf after identifying the leaf are 2 things on the bugs little brain.
 
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The one I have would be the Eugenia myrtifolia 'Variegata'
http://www.onlineplantguide.com/Plant-Details/4487/

I doubt these are Nematodes. I'm actually able force these little bugs out of their hiding and they are crawling around on small legs. These bugs are round with a flat top. I do have a video for those interested.

There will be no cure for the already affected leaves, but it would be nice to get rid of the bugs and let the plant develop some fresh and healthy leaves.
 
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The one I have would be the Eugenia myrtifolia 'Variegata'
http://www.onlineplantguide.com/Plant-Details/4487/

I doubt these are Nematodes. I'm actually able force these little bugs out of their hiding and they are crawling around on small legs. These bugs are round with a flat top. I do have a video for those interested.

There will be no cure for the already affected leaves, but it would be nice to get rid of the bugs and let the plant develop some fresh and healthy leaves.
Sorry I was not more clear, what I read was that galling insects are in a unique group of which nema are a member. This was meant to draw parallels to your mystery bugs. They (galling group) are able to control the cells of the plant (which causes the gall) by chemical mutagenic means. Like a horror movie where the monster can transform people into something else. Its an insect superpower. It is also a mechanism for protection that makes them tough to get at. I am not aware of a systemic insecticide for your bugs because my focus is mainly veggies. I believe something may exist and where they are ornamental it may serve to weaken the bugs as part of a multi-part cultural process to control them. This was why I was interested in the plant type. There may well be a commonly used systemic for that plant. In the nema control, temps and moisture increase their multiplication for example, and as they hatch and are weak they meet my thyme oil and fail to function further. Perhaps once identified, this idea of timing controls for that insect will make a big difference.
 
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This is exactly it! Thank you so much for the research and time on this. I will try some of the suggested and update this post.
 
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