Consensus on Orthene for fungus knats a NO NO ?

[greenpassion]

I have two newer orchids living with my other ones that have been in S/H for months now. I have noticed that I have fungus gnats flying around, and as I know S/H won't support their living requirements, they have to be from the new milts I received planted in bark and moss. In reading thru some posts in this forum, someone, (maybe Ray) suggested using Orthene to kill the larvae. In looking it up I came across (in a bromelaide discussion board) someone expounding on the dangers of using orthene on orchids other than phals and various thick leaved plants. If this is so, what would be an alternative to using orthene?

[Gin]

For gnats I have used the yellow sticky traps also the mosquito dunk treated water seems to get rid of them not seen any around for a long time . Gin

[zxyqu]

Agreed with Gin on this one. Use the traps to take care of those flying around (or if you have a greenhouse or enclosed space, I prefer carnivorous traps like drosera), and mosquito dunks for your water supply. Has really been working ever since my problem exploded. Almost completely gone now.

[Ray]

To answer the original question, I have never seen Orthene hurt any orchid.

It should be quite effective on fungus gnat adults, but I'd like to offer a couple of more things to consider:

The idea behind the sticky traps is to reduce the adult population, and the mosquito dunks infect the critters with bacillus thuringiensis v. israelensis, a natural way to eliminate them, but to me, their mere presence indicates that there is fungus growing in the medium, which means it's decomposing, so they are the "canary in the coal mine", warning you about a need to repot.

[greenpassion]

I have to respond to Ray's post in this matter. I am convinced that it's more than likely that the gnats are from the two orchids that I just received that are planted in moss/bark. I want to repot them, but they are both currently blooming. I want to wait until they are finished, then put them into S/H. As far as the suggestion of tape to catch the adults, my orchids are a center piece in my living area. I grow them on an island under track lighting, and this divides my kitchen from my living room. The idea of nasty tape being seen is not something I'd want to do. I'm going to look for Orthene. Do they make it water soluble-as an additive to the water I'd use to flush and water them?

[silken]

Originally Posted by greenpassion

I have to respond to Ray's post in this matter. I am convinced that it's more than likely that the gnats are from the two orchids that I just received that are planted in moss/bark. I want to repot them, but they are both currently blooming. I want to wait until they are finished, then put them into S/H. As far as the suggestion of tape to catch the adults, my orchids are a center piece in my living area. I grow them on an island under track lighting, and this divides my kitchen from my living room. The idea of nasty tape being seen is not something I'd want to do. I'm going to look for Orthene. Do they make it water soluble-as an additive to the water I'd use to flush and water them?

I have used Malathion with great success to get rid of the adults and the larva. Granted it is stinky, but the smell will go away in a day or so. I spritz the air around the plant to drop the adults and then spritz the top of the media enough to wet it somewhat. That has usually been the end of them although you may want to spritz the media again in a week in case some eggs survived and hatched. But I think the Malathion would still be present in the media and kill any new hatchlings anyways.

[Leafmite]

Butterworts with round leaves are great at gettting rid of fungus gnats. I bought mine from an orchid vender.

[NYCorchidman]

Originally Posted by Leafmite

Butterworts with round leaves are great at gettting rid of fungus gnats. I bought mine from an orchid vender.

I would love to try these plants. I have venus fly trap and pitchers, but they are only good for much bigger bugs like houseflies and small bettles. It's amazing the variety of bugs I see in the apartment that come in through the open windows.

[Susie11]

Humm, I have recently repotted and I am seeing alot of these things flying around. I don't over water my phals which is were they mainly are. They get it only when the roots are showing white and then it is poured through the top of the medium for a while. They don't sit in water and they don't appear to be soaking wet -evenly moist I would say so I don't see why they are so prolific. I hate them -I really do. They ruin an otherwise pleasant experience. Maybe I should get the traps too?

[zxyqu]

I really do appreciate Rays stance on this, but in my conditions, these little buggers occur independent of moss breakdown. I only use moss and S/H an the collection just turned over to new media and yet, I still have some of these moving around. All in all I have no idea where these buggers hideout. So I'd recommend treating both the adults and with the dunks, and to also stay on top of reporting just in case.