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I think I finally have fungus gnats. Had done so well until now. Some cuttings started to die back and I pulled some out to check on them and little black flying bugs went scattering. 

Dang.

Nichole, check the lower end of the cutting to see if it is rotten. Peal back the soft bark and you will see the tiny whiteish larvea (small worm looking thing that moves). This will let you know if it's the gnats that caused the problem.
"gene"

I think I found a couple. I'm now worried about a large tote of "sleeping" rooted cuttings I have. 
All the potted cuttings that I had been moving outside on nice days have lots of little black flying critters all over them.

Looks like my new greenhouse is going to get fitted with gnat traps.

I recommend BT or BTI  (bacillus thurengiensis (israeliensis)).  I use a product called Thuricide to have a colony of that going in my watering can (for cuttings) most of the time, even as a preventative measure.  There are lots of products (e.g. Gnatrol and many others) listed on the forum here.  Good luck.  Gene just posted about some other agent that kills the gnats in another thread today.  Good luck Nichole.

Mike   central NY state, zone 5

Just picked some up on amazon, thanks Mike. 
Apple cider placed everywhere.

This means war!

I use the BT on some of my plants, too, and do recommend it as an organic alternative for controlling many types of pests, but be aware that it doesn't kill the adults - only the larvae.  It works by paralyzing the mouths of insects that feed on the leaves and roots, so they stop feeding and die in a couple of days.  Also, it's very possible (I would even say, "likely", especially if it's indoor plants still rooting), that the fungus gnats were present in the medium when you purchased it, so I'd be very careful using the same medium with other/future plants.  It's not uncommon when purchasing some "inferior" coco coir, or the like, to get fungus gnats with it!  Good luck on eradicating those little buggers - I hate them with a vengence! :)

 ugly as it may look, get yourself some fly traps.. at least they catch the adults (meaning no more 100 egges each) will be layed down.. let them almost dry up , water from the bottoms and pray... it is awful...

The medium I purchased is promix BX

Promix is a great product, and I believe it's a "soiless" medium which would normally not contain the fungus gnat larvae.  Did you mix the Promix with anything like peat, coir, or sphagnum? 

I mixed it with pine bark. Would gnats travel in that?

They may have hitched a ride from outside, too. Is that possible?
They've been going out on sunny days, then back inside because our nights are still in the 40s. The little critters are especially bad in those same gallon containers.

Hard to see, but there are three larvae at the end of this cutting. I'm including a still image and a video in case there are any other newbies out there (like me) who would find this helpful.






Both the pine bark and an "Outside Hitcher" are possibilities, but if I were a gambling man, I'd put my money on the pine bark.

Here's a good overview on Fungus Gnats:

http://www.greenhouse.cornell.edu/pests/pdfs/insects/FG.pdf

Note the section on "Cultural Control" which says, "For fungus gnat management, avoid immature composts (<1yr old), including composted pine bark mix."

 

*shakes fist at pine bark*

What should I use in place of pine bark? I was putting it at the bottom of my containers, then the promix and cutting, with a layer of pine bark on top to help retain moisture. Maybe nothing at all, since moisture is the gnats best friend.

Thanks Noss - fixed the video settings. You should be able to see it now.

I am going to water everyone with mosquito dunks. I'll water my rooting riot cubes and potted cuttings with the dunked water in the morning.

That's a tough one, since there's really nothing wrong with pine bark, coir, moss, etc., per se.  It's just that, every once in a while, you can get an infested batch and it wrecks havoc on the plants, especially young and/or diseased plants that aren't as resistant.  You can continue to use the Pine Bark, but if you're going to use the same batch/bag, I would definately sterilize it first, either by baking in the oven (I believe the temp needs to reach 180* F for 30 minutes to kill the larvae) or by soaking in a bleach solution (I believe it's something like 1 part bleach to 9 or 10 parts water). 

That batch of pine bark is long gone. Are there any sources that are tried and true, or at the very least, maybe less likely to bring on an infestation? I picked up the (probably) guilty bag of orchid bark from lowes. I'd gotten Black Gold in the past with no issues, but have been having a hard time finding it in larger sizes.

That's another tough question! :)

I've been using the Black Gold, also, purchased from HD, and I haven't had any problems yet.  I usually just recommend staying away from the "cheapo" stuff, but it's entirely possible that the fungus gnat larvae didn't even make it into the pine bark until AFTER it got to Lowes.  So, if the HD I buy from gets some infestation, it's entirely possible that my next bag of Black Gold will be infested, too.  I just recommend staying away from the cheap stuff since I believe there's less of a chance of the larvae being present from the manufacturer.

Maybe it has more to do with location. The orchid bark from lowes wasn't cheapo stuff, but it was at lowes, next to other cheapo stuff. And I'm sure it was snuggled up next to pallets of other cheapo stuff on the shipping trucks.

Maybe I'll check out the local hydroponics store and see what they carry.

I went through 26 of my 'sleeping' cuttings and tossed out all but 9. Not enough good roots to salvage any of the others - they were the youngest and therefore most vulnerable. I have another 25 cuttings with lots of leaves but I'm sure they are getting infested now, too. I have a lot of reading to do tomorrow.

Of the 9 sleepy cuttings left I feel like I should get in there and do something but fear doing more harm than good. The downside to the rooting riot cubes is it makes getting to the wood difficult.

Thanks for the help.

Location can play a big part.  With all the plants HD & Lowes have being delivered from multiple sources, it would be very easy for them to get a shipment of plants that are already infested and for the adults to find their way to the pine bark, other plants, etc. and lay their eggs.  Goodluck!

Dinner is served!

I found some of those worms on a stalled Gino's cutting. I clipped the bottom, and left it out to callus again. The cutting at the cut looked good.

I hope they didn't get into everything.


I thought Nematodes were BAD?!?  or are these genetically modified to not cause RKN?


Quote:
Originally Posted by Nichole
Dinner is served!

I was assured by the older gentleman in the store (who works for WSU in the horticulture dept) that these are different. He said there are a multitude varieties of nematodes, and RKN is different. These ones are beneficial, living in the soil, not roots, feeding off other parasitic organisms.

I called again, spoke with someone else, who assured me it's not the same thing - only beneficial.

Searching the net shows predatory nematodes as well as parasitic nematides. RKN is parasitic - living off the host plant.

If they are all incorrect I will definitely let you all know.

Quote:
Originally Posted by ChillyNPhilly
I found some of those worms on a stalled Gino's cutting. I clipped the bottom, and left it out to callus again. The cutting at the cut looked good.

I hope they didn't get into everything.


I hope so too. My cuttings are surrounded by root ruit cubes. I don't have the mad skills required to remove the cube without hurting the roots. I'd need sharper tools.

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  • KK

Quote:
Originally Posted by Nichole
I think I finally have fungus gnats. Had done so well until now. Some cuttings started to die back and I pulled some out to check on them and little black flying bugs went scattering. 

Dang.


Do they have black heads?






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