10 trees - orange / lemon / lime - margarita garden.
San Diego
Had a bad infestation of leaf miners last year. I hoped to avoid this year but they just showed up - alot.
One tree that was most harmed last year is heavily infected this year - just in the last 3 days.
Some (maybe 10%) of the leaves have holes shaped like the miner tracks telling me that I have some beneficial critter that likes them.......but not nearly enough to win the battle.
I'd like to be environmentally conscious but I'd also use a shotgun if I thought that would work.
What to do.......
Insecticide? / spray on? / systemic - sacrifice this year's crop?
Neem Oil?
Remove leaves - a few would be almost bare....?
I think I also read that disturbing the soil under might help - yes?
Any and all suggestions appreciated.
David

To my knowledge, leaf miners do no damage, except of course to the looks of the leaves.

Leaf Miners can be a major problem in California. Here's what University of California Pest Management says:

https://ipm.ucanr.edu/PMG/PEST...

Wow! I had no clue that they were such a problem for Ca.! Apologies, if my answer seemed flippant.

talerco said: 10 trees - orange / lemon / lime - margarita garden.
San Diego
Had a bad infestation of leaf miners last year. I hoped to avoid this year but they just showed up - alot.
One tree that was most harmed last year is heavily infected this year - just in the last 3 days.
Some (maybe 10%) of the leaves have holes shaped like the miner tracks telling me that I have some beneficial critter that likes them.......but not nearly enough to win the battle.
I'd like to be environmentally conscious but I'd also use a shotgun if I thought that would work.
What to do.......
Insecticide? / spray on? / systemic - sacrifice this year's crop?
Neem Oil?
Remove leaves - a few would be almost bare....?
I think I also read that disturbing the soil under might help - yes?
Any and all suggestions appreciated.
David

Hi Neem Oil is an Antifeedant, it might a might work.

Thanks so much - all. Don't feel bad terrafirma...... but my trees are in about 5 years old and when most leaves are affected they get near death.
They were coming back healthy and have fruit - until a few days ago. I hate to spray and won'y use systemic while fruiting so....
I'll try the neem oil on the newer leaves - and selective leaf removal.
I throw the affected leaves away. I think I read that you can crush the trails and leave the leaf. Does anyone know about that? Can you pinch the life out of those little suckers?
Maybe cut the part with trails and leave the rest of the leaf? - like I have nothing else to do?
I'll report back.

If you haven't used Neem before, read ALL the instructions and warnings. Spraying when its hot, humid, wet, sunny... can all burn the leaves.

I'm disappoointed the article suggested Imidacloprid as an option. Its a pretty deadly general systemic. It will kill the leaf miners but also the bees, butterflies, birds and anything else that feeds on the flowers or fruit (including you).

Crushing leaf miners can work- I do it for something small like columbine- I can't imagine crushing all the leaf miners on a tree.
From what I've read, you want to use a neem product like this specifically with azidarachtin, not just any 'neem oil'
https://generalhydroponics.com...
and with your trees, it would be worth buying a good quality product in bigger quantity anyway than single quart spray bottles from walmart for example.
Lucy68, do you read the same about neem products?

https://www.gardenmyths.com/ne...

Sometimes there is no choice if you want to save a tree and have to use Imidacloprid as a last resort. I have a huge Magnolia tree that's over 60 years old now that had a severe infestation of scale bad enough that it would have killed the tree if left untreated. Imidacloprid has to be applied in early spring to get the magnolia scale while they're still soft, once they harden up into the white blobs it has no effect. But I waited until after all the flowers dropped before applying to avoid poisoning any pollinators, and that was still early enough to work.

It would have been impossible to get any type of spray everywhere on a 50' x 50' tree with multiple trunks to finally get rid of the scale any other way.

sallyg said:
Lucy68, do you read the same about neem products?

I use 100% Neem (have to keep it refrigerated). Azadirachtin is the active component. There are a lot of products that contain Neem but you want the real deal 100% nothing added Neem.

I appreciate all the replies and advise. VERY frustrated.
5-6 year old trees. On some EVERY new leaf has miner trails and curling.
I tried everything else and finally today resorted to systemic poison - Imidacloprid. I am giving up eating any fruit this year and I'll get rid of any flowers to protect bees etc.
My question for now.....
This is the second year of what seems like a total infestation of leaf miners. How do I prevent this next year?
I think somewhere along the line I read that they do hang out in the soil. Is this where they spend the winter? (Remember Southern Califonia - only kinda 'winter')
Can I apply anything to the soil? - At what time of the year?
I'm think maybe a propane torch to the soil around each plant at some point - or at several points...
Knowledge appreciated!

They hang out on the plant not the soil. The best thing to do for them is……… nothing. Keep the plant as healthy as possible and ignore the crinkled leaves. They won't kill the plant or even set it back much unless every single new leaf is reduced to a midrib. Barring that, the tree will survive. Just ignore them.