Leafminers and Spinosad

[kwselke]

Leafminers are a major problem for me every year. I've read extensively about them and pretty much come to the conclusion that I just has to live with them. In the last week or two the biological control Spinosad has popped on to my radar screen. Supposedly it kills through ingestion but also secondarily on contact. It is labeled for control of leafminers on tomatoes with a one day wait for harvest after application. I am skeptical that it can do much to control leafminers. I guess the larva must have to eat their way out of the leaves to continue their life cycle. Does anyone have experience using Spinosad to control leafminers? Would I just be wasting my money giving it a try? Normally the only bug stuff I use on tomatoes is BT.

[feldon30]

Originally Posted by kwselke

I guess the larva must have to eat their way out of the leaves to continue their life cycle.

That is correct. Do you think the leaf miners are reducing your production? The first year, I started picking off leaves with leaf miner damage. Before long, I stopped, because I was in danger of completely denuding my plants. Last fall I saw maybe 10% as much leaf miner activity as the spring.

Although I do not like Sevin because it can kill honeybees, I've heard of using an initial shot of it at transplant on the soil (mulch!) and plants to keep away cutworms, flea beetles, and other bugs just in the first 2-3 weeks after transplant. Of course it rains every 3-4 days in Houston, so I guess reapplication would be necessary?

[kwselke]

Feldon,

Leafminers wiped out three sets of starter plants for my fall crop last year. I've normally thought that the Fourth of July ended my production in Houston due to the heat and pests, leafminers being high on the pest list.

In trying to answer my own question I found this article on Spinosad at Cornell's website. http://www.nysaes.cornell.edu/pp/res...13spinosad.php

It appears that Spinosad is taken up to a certain extent by the leaf material itself, but is not considered systemic.

I think I'll give it a try, unless someone here warns me off. With heat setting hybrids, Daconil, and Spinosad I might be able to harvest well into August.

[gardenmaniac]

Remember that once you see the tunneling in the leaves, it is usually too late. The worm is already gone. Look at the lines and you will see the worm inside if it is there, then just squish it inside the leaf. Removing the leaves once the worm is gone just takes valuable leaves off your plants. This is what our local citrus nursey told me. I have never been able to find a worm in the tunnel before. I always miss them. They bother my citrus more than my veggies. But other than cosmetic damage, I've never had decreased production. Not saying that isn't possible, however. If you use it, let us know if it works for you.

Tiffanie

[kwselke]

Check out the link to Cornell's Material Fact Sheet on Spinosad. The microbial bug toxin is actually absorbed into the leaf matter. Therefore it should kill the little maggots inside of the leaf. Since it is microbial as opposed to synthetic it is supposed in the same class of pesticide as BT, and is considered organic. It's supposed to last longer than BT and may be used instead of it. I just bought a bottle and will read the full pullout label. If I do not like what I read, I'll take the stuff back.

Edit:

I purchased a 16 ounce bottle of Green Light Lawn and Garden Spray Spinosad. The price was $12.99. Per the label, the dilution rate is to be 4 tablespoons per gallon of water. The maximum number of applications for tomatoes is six per season. Days wait before reapplication is four. Minimum days to harvest is one.

The folks at my local full service nursery were well aware of the stuff, but due to an ownership change the purchasing is no longer done locally and they only had it in hose end sprayer form for application to fruit trees. Using a hose end sprayer on my seven plants is a bit of overkill. They apologized for not having the form that could be mixed in a small sprayer and sent me to a full service hardware store that had it in stock.

The more I read about this organic pest control the more I like about it.

[gardenmaniac]

It sounds like good stuff. I might consider it for my citrus. I thankfully only have minimal problems with my herbs and veggies. Thanks for the info.

Tiffanie

[kwselke]

They also put Spinosad in fire ant bait. The ants eat it and their nervous systems are excited then they die of exhaustion within three days. For some reason I love thinking about the way fire ants might die.

[feldon30]

For controlled areas, I just put the kettle on. Boiling them alive seems too good for them.

[FlipTX]

Last year leafminers decimated my pepper plants and did a lot of damage to my tomato and squash plants. Many leaves were so "mined" that they turned yellow and wilted.

This season I started using the Green Light spinosad product. I see plenty of the adults buzzing around my plants but I see very few "mines" on the leaves. Is it the spinosad? Maybe! I haven't done anything else different from last year. I just make sure not to spray when a plant is attracting bees. I wouldn't spray a flowering squash or cucumber plant, for example.

[kwselke]

Last Sunday I noticed the first signs of leafminers in my tomato patch. I mixed up a quart of Spinosad in a hand sprayer and treated the one plant. The one treatment appears to have put a stop to the damage. It works for me.

[Joel5000]

I have used Spinosad (Monterey Garden Insect Spray) the last two years, and I've been very happy with it. I usually apply it when I spot the first hornworm, and then another application about three weeks later. I've had very few insect problems (other than stinkbug damage).

[kwselke]

I've had my ups and downs with leaf miners. The last two seasons, work and bad weather kept me from pursuing the Spinosad question. This afternoon I was checking my plants which have been in for maybe 12 days and there on a beautiful Sweet 100 is fresh leaf miner damage. I cut the afflicted leaves and bagged them. The pictures look like I caught the buggers while still in the leaves. I then applied a proper mix of Green Light Spinosad to all my plants. I found a little damage on a couple of other plants I was hardening off for a friend who lives well north of me. There has been little talk of this product here. Have I already killed my plants.

[duajones]

I sprayed my plants a couple of weeks ago at the first sign of leaf miner damage. I havent noticed any further damage since that time, if so it is real minimal. I cant say that I speak for the product, have to wait and try it some more