Ok, i have leaf miners on a few of my orange, and lime trees . I know that the best way to get rid of them is not to. Leave them alone. My question is will they ever go away? die off? etc? Its been getting cold here at night( lower 30'sF) Will the cold weather kill them off? My trees are old. Over 35 years plus. And still produce mass amounts of fruit. Is there anything that i can do to battle these little guys?


mark

Leaf miners are nuisance pests and have not been known to affect yield. I would leave them alone. The upper 20's to low 30's doesn't affect them, in fact it drives them to the available evergreens, and in this case, citruses.

Today it is blisteringly hot in my yard, compared to days before. We are in the low 70's today, a couple of days ago, in the upper 40's. With the very cold ground barely catching up to this hot spell in mid-winter, I am sure to have significant leaf drop.

Leafminers usually disappear with the first frost & you will begin to see them again in June or July. There is a chemical they use in Florida that is supposed to be very effective against leafminer. Admire Pro is the chemical, but only available to the nursery trade.



http://www.bayeradmirepro.com/

I have been battling them for the past year here in Florida and while there are studies that show they have not caused statistically significant reduction in yields from mature trees, they can have significant effects on young trees and open the leaves up to disease in any trees that they infect.

The most effective control short of the abemectin (active ingredient in Admire)-- which is a systemic, is horticultural oil. It does not kill the miners it just keeps the adult moth from laying eggs on the leaves since they do not like the oily surface.

There is one other insecticide that is availible to the average person-- spinosad --(in Fertilome Bagworm and Borer) made from fermenting a soil bacteria that is somewhat effective, however according to the label, you are not suppose to apply it more than 6 times per yr. It does not persist very long after application with a half life of less than 2 days, but mixing it with hort. oil will help extend that some.

If you just want the satisfaction of personally squashing a few -- get a magnifying glass and a needle and dig a few out. I did that for several day so I know how fast they multiply--but it was hopeless, but it made me feel better!

I am going to try one new trick this summer when new flushes start-- I had my wife sew me a dozen sleeves out of the frost blanket material. I plan to put the sleeves over new growth until the leaves are hardened-- the moth actually lays the egs on leaves when they are less than an inch long-- so If I can keep them off during the first week or two they should be safe from the miners.

Good luck --- Skeet

I had a very severe infestation last summer and, on new citrus trees, they were doing a significant amount of damage to all the new growth. One application of Monterey Garden Spray got rid of them. I'll see if any come back in the spring. Available at Peaceful Valley Garden Supply for 11.99
http://www.groworganic.com/item_PBI800_MontereyGardenSprayConcentratePi.html

Hi Douglasyo,
According to the link you provided, the active ingredient in that is the spinosad I mentioned earlier. It will do a good job of killing what is there, but in most environments it will not persist more than a few days to a week, especially here in the hot and humid south. I do not know why EPA has put a limit of 6 applications per year on it, but it is probably to prevent insects from becoming resistant.

It is a "safe" pesticide with an acute toxicity level close to that of table salt, and it is considered organic since it is extracted from a soil bacteria.

Skeet