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The Corroboree

Biological control for fungus gnats in garden soil Australia?

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I have unbelievable amounts of fungal gnat larvae in my garden soil. Have had for years. But it's now getting in the way of me establishing outdoor Stropharia beds in my yard and I'm over it.

Anyone have experience with predatory mites for knocking fungus gnat larvae on the head- specifically in garden soil ( not potted plant/ greenhouse ) environments?


Other possibilities for dealing with the ongoing infestation have been rejected, but have included letting the neighbours chooks in the yard for two or three gnat breeding cycles, dernching the whole place in neem on a regular basis, and totally razing the surrounding vegetation so that the soil is more exposed and doesn't provide habitat

Even more relevant would be tips and hacks from NNSW and surrounds

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Had the same situation, parasitic nematodes (Steinernema feltiae) really did the trick. Plus the video is FREAKING AWESOME!

Got them at the local garden store for $20.00. Basically what you get is a plastic bag with a little bit of thin sponge in it, folded in half, and in the middle there is a daub of pink goop. You mix the pink goop with a half gallon of water, and you have enough nematode-water to treat 1000 square feet of gnat-infested land!

They go right to work on the maggots, and every last gnat was gone in three weeks. The nematodes are active in the soil for three weeks . . . before they die out, for lack of any more maggots to parasitize.


(My FB post over Halloween)

More Green Adventures. Noting transparent little worms, 3mm long, with black dot at head. Identified them as fungus gnat larvae. Pest control is always a headache in the basement. Fortunately, we live in 2015, and I can easily get a package of Steinernema feltiae, beneficial nematodes, which will eat them. The damage is heart-breakingly bad though: each fallen seedling has a gnat-maggot at its base, the roots are gnawed off, and there a small cavity in the bottom where the maggot is attacking the body of the doomed seedling. Lost 25-50% of my crop already. #1 priority tomorrow morning is to get those steinernemas going!
EXTREMELY GRAPHIC little movie about what the STEINERNEMA's do inside the Bradysia/Sciaridae larvae . . .. NO NEED FOR ANY MORE HORROR MOVIES THIS HALLOWEEN THANKS!!!! You watch this little slice of reality, Hollywood Hellraisers can do NOTHING FOR YOU.

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take a jar, put some apple cider vinegar in it

take a clear plastic bag, put it over the jar opening.

Tape tightly around the edges.

Poke a small hole in the center of the plastic.

place in warm area near gnats.

they will fly in and not get out

strangely gratifying to see a bunch of then drowned in there over a day or two

works all day and night, tirelessly, almost for free!!

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