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Rogue11
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Best way to get rid of Fungus gnat larvae?

What's the best way to get rid of Fungus gnat larvae? I never seen any of the gnats themselves, but I found little worms that seem to be their larvea in the soil when I removed the roots of a plant that had been eaten by snails.

Thanks

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Kisal
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If you haven't seen gnats, then my guess would be that the "little worms" are something else. Perhaps they are nematodes of some sort? :?

That's just a stab-in-the-dark guess, though. Lots of different critters live in the soil. :)
"Isn't it enough to see that a garden is beautiful without having to believe that there are fairies at the bottom of it too?" - Douglas Adams

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Rogue11
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Actually what I mean is that I haven't seen any because I haven't really paid attention to it. I just came across the worms that look like tiny maggots when I was digging in the soil. It's in a bed that I had only prepared a few weeks ago with new soil and compost.
I didn't know what the worms were but after some searching came across articles about fungus gnats and pictures of their larvae look very much like what I have in my soil.

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Kisal
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Well, I certainly could be entirely wrong, but I've never heard of fungus gnats being a problem outdoors, only in greenhouses and indoor container-grown plants. So, are we talking about an in-ground garden, or container plants in a greenhouse or in your home? Fungus gnats are usually quite noticeable in any indoor setting.

The larvae cannot live in dry soil. They just shrivel up and die without sufficient moisture. They don't live very deep in the soil, mostly just in the top couple of inches. If you allow that much to dry, you should be able to get rid of them ... if they are the larvae of fungus gnats. Some people say they are able to control fungus gnats by adding cinnamon and/or chamomile to the water used on the plants. You might be able to control the larvae by using a neem oil solution as a soil drench, although I'm not sure whether that would also damage helpful soil dwellers, such as earthworms.

There are similar flies & gnats that live outdoors in very moist soil. There are some kind of gnats that live in the soil around my birdbath, which is always damp because I dump and clean the birdbath almost every day. I don't bother them, because the birds seem to enjoy eating them. They produce clouds of some kind of little fly-like things in May or June each year, but the swarms tend to hover in the shade, by the birdbath, and don't bother me. They don't seem to be a problem for any of the plants growing in that area, either. But, that's just my own experience with gnats outdoors. I haven't had a problem with them indoors, but I'm careful not to overwater my plants. I practice benign neglect. :lol:

Since you're in California, you may find some useful information in this material from UCDavis:

https://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7448.html
Last edited by Kisal on Fri Apr 29, 2011 12:19 am, edited 1 time in total.
"Isn't it enough to see that a garden is beautiful without having to believe that there are fairies at the bottom of it too?" - Douglas Adams

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Rogue11
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thanks I'll check out those notes.



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