Fungus gnats in finished vermicompost...

[SpicySativa]

What's up fellow worm wranglers?

I'm about ready to harvest a batch of worm castings, but I've got a minor fungus gnat infestation in my bin. Do any of you have a tried and true method for dealing with fungus gnat larvae and eggs in harvested castings? I've been keeping the infestation "controlled" by using mosquito dunk water (lightly sprayed) and copious amounts of dry bedding (peat and paper), but they are still around...

Here's an approach I thought of... Think this might work?


-Stop feeding the bin for 2-3 weeks.

-Lay a big sheet of *"no see um" netting in a 5-gal bucket*

-Screen castings into the bucket (using 1/8" mesh) to remove most of the worms and unprocessed bedding

-Gather the edges of the netting and tie them off with a zip tie (essentially making a sac-o-castings-in-a-bucket).

-Secure another piece of "no see um" netting over the top of the bucket to prevent any fliers from reaching the moist material.

-Wait about 4 weeks for all worm cocoons to hatch. (maybe leave an apple core or something for them to munch on when they hatch).

-Re screen the castings to remove the newly hatched worms and reveal clean, finished, pest-free castings.


My theory is that in this time fungus gnats of *all stages will have had time to hatch, *pupate, and emerge as adults. The netting stretched tight over the castings will (hopefully) prevent the adults from mating, and thus break the life cycle once the adults die off.*

Am I making this way more complicated than it needs to be?*

Suggestions?

Thanks in advance.

 

[canna woop!]

i have seen a worm's bin (in a children's garden) where they put a plastic over the surface of the medium, there are no fungus gnat fliers when you pull it back. It's an outdoor bin, with lots of leaves molding, red worms and spiders

 

[RanchoDeluxe]

Must be that time of year or something?

Check this out dude. I've got a bunch of leaf litter outside that I know is chock full of fungus gnats. I bring it inside and use it as mulch anyway. I'll hang some yellow sticky traps and spray the soil surface w/ some neem a few times...really not much of a problem. Fungus gnats actually prefer dead, decaying material to consume. They cause minimal, if any damage to a healthy cannabis plant. Small seedlings and clones are the only thing susceptible to them. Have I ever lost a cut to fungus gnats...NO!

Why do I even bother to kill them you may ask? If I don't the population can get way out of hand and they will end up getting stuck to my buds.

I'm curious if anyone feels like they have ever lost a plant or has seen extensive damage by what they believe to be fungus gnats?

Sorry about the rant...this is the third or fourth fungus gnat thread this week, and I really don't understand the lengths some people go to in order to control them.

Am I making this way more complicated than it needs to be?*

LOL! just saw that last quote...IMHO...yes.

 

[SpicySativa]

I am aware that gnats don't cause established plants much harm, but they DO harm small cuttings and seedlings (like a couple of my tomato starts that got rampaged). Treating potted plants is easy, but i cant exactly do a BTi drench of my worm bin.

The bin is the source of the infestation that's buzzing around my outdoor veggie garden, house plants, and sticky buds in the flowering cabinet. They've gotta go. The bins ready to be harvested, but I need a dry solution to kill off the larvae before I start spreading it around my plants. Simple as that.

 

[Nader]

i wonder how Hypoaspis miles would perform in a worm bin. They're wonderful and have saved my ass.. the only warnings I remember was not too cold and they'll die in a flood.

 

[SpicySativa]

Nader- H. miles could be worth a try. I think I might actually have a "natural" population of predatory mites in the bin, but they dont seem seem to be keeping up with the gnats. They are light brown, fast, and I've seen them swarmed around a dead fungus gnat larvae.

I just unleashed the wrath of one million nematodes last night... We'll see how that works.

 

[RanchoDeluxe]

Well then...you get em killer!

 

[BlueJayWay]

I'm wondering if cutting or seed/seedling death due to "fungus gnat larvae" are actually misdiagnosed nematode attacks, you know, the bad ones.....

population can get way out of hand and they will end up getting stuck to my buds.

hehe...hehe, yup, sticky buds, natures own sticky traps!

 

[BlueJayWay]

Nader- H. miles could be worth a try. I think I might actually have a "natural" population of predatory mites in the bin, but they dont seem seem to be keeping up with the gnats. They are light brown, fast, and I've seen them swarmed around a dead fungus gnat larvae.

I just unleashed the wrath of one million nematodes last night... We'll see how that works.

I've found predatory nematodes to be very effective.

 

[Harry Hoosier]

Got neem meal? If so, take an 1/8th to 1/4 cup and dust the bin material.

 

[supermanlives]

I am having some issues too. moved my bin outdoors are the flies started drinking more of my beer than me and taking baths lol. I have neem and karanja . thanks will try it

 

[SpicySativa]

I routinely dust with a neem/mosquito dunk mixture I mash up with a mortar and pestle.

 

[SpicySativa]

Well, following the nematode dose, I see very few gnat larvae in my bin, but it's still buzzing with flyers. Seems like their numbers are going down as I let the bin "mature" without added food. I think I'll go ahead and harvest the bin this evening. The castings look fantastic. Black and crumbly with a deep rich earthy smell.

 

[Vandenberg]

A ten year old post...this has ALWAYS worked for me.

Mosquito Bits work immediately and the larvae of fungus gnats die within contact with-in just 24 hours of nibbling on the baited bits.
It is a very cheap, simple, and effective formula to control fungus gnats.
It kills larvae in the soil before they become adults ( die,die you little bastards,die!) so it takes only 1 day to control the population of fungus gnats.
it is relatively inexpensive and it is very easy to use.
It will work very well just try this if you are infested with fungus infestation.
One can soak these in water for a few hours and strain and apply by spraying/incorporating the resultant voodoo juice into your still active vermicompost bin. A simple and uncomplicated solution. (in answer to original thread starter).

Bti \ CDC

Learn about Bti (Bacillus thuringiensis israelensis): product types; how it works; its safety for people, pets, animals, aquatic life, and insects including honeybees.

www.cdc.gov

Vandenberg

 

[Three Berries]

A ten year old post...this has ALWAYS worked for me.

Mosquito Bits work immediately and the larvae of fungus gnats die within contact with-in just 24 hours of nibbling on the baited bits.
It is a very cheap, simple, and effective formula to control fungus gnats.
It kills larvae in the soil before they become adults ( die,die you little bastards,die!) so it takes only 1 day to control the population of fungus gnats.
it is relatively inexpensive and it is very easy to use.
It will work very well just try this if you are infested with fungus infestation.
One can soak these in water for a few hours and strain and apply by spraying/incorporating the resultant voodoo juice into your still active vermicompost bin. A simple and uncomplicated solution. (in answer to original thread starter).
View attachment 18809077


Vandenberg

I just add it to my water to add to the soil, don't bother straining it out. it works most excellent.

I don't know though if you would want to put it in a compost bin as it would kill a lot of beneficial bugs too?

 

[Vandenberg]

My experiences with bti is with actively, currently in-use soil medias and not in worm bins.
You are probably right about potentially killing some beneficials, it probably does have effects on other species besides skeeters and gnats, but perhaps not. An inspired thought and question though. I don't currently know the answer, but I think I'm going to seek out the answer.

Vandenberg

 

[Vandenberg]

Bacillus thuringiensis serotype israelensis (Bti) is a group of bacteria used as biological control agents for larvae stages of certain dipterans. Bti produces toxins which are effective in killing various species of mosquitoes, fungus gnats, and blackflies, while having almost no effect on other organisms. The major advantage of B. thuringiensis products is that they are thought to affect few non-target species. However, even though Bti may have minimal direct effects on non-target organisms, it may potentially be associated with knock-on effects on food webs and other ecosystem properties, including biodiversity and ecosystem functioning.[1]

Bacillus thuringiensis - Wikipedia

en.m.wikipedia.org

Vandenberg

 

[FletchF.Fletch]

Can also find Bt var.i in powdered form under the trade name Gnatrol. It mixes easily with water and can be used as a preinoculant against Fungus Gnats and other soil borne pests in Soil, Coco, or Rockwool.

 

[Vandenberg]

Pot growers:
This BTI is guaranteed to kill them punk ass bitch fungus gnats.
Feel free to laugh in their little faces as you give them a refreshing drink.
Bye-Bye Fly-guy! ;-)

Vandenberg

 

[tentgrower]

Can also find Bt var.i in powdered form under the trade name Gnatrol. It mixes easily with water and can be used as a preinoculant against Fungus Gnats and other soil borne pests in Soil, Coco, or Rockwool.

I just ordered 1/4# of gnatrol off ebay for $23 from a vendor that breaks down the 16# containers valent bioscience sells it in for $500 or so. It's $8.54 per 1/4# in the 16# tub from valent so it's close to a 300% markup @$23 on ebay.. Gnatrol's application rate is 3.64g-7.28g/gallon for heavy infestations or .9g-1.8g/gallon for standard application. If applied at full strength 1/4# will get me 15.38 gallons of solution. The high end of the regular application rate of 1.8g/gallon would get me 62.22 gallons of solution. When I compared the value of the mosquito bits 30z container with the 1/4# gnatrol (mosquito bits were about $4 more at $28) the gnatrol seemed a much better choice. I'm hoping this stuff works as well as I hear it does