Bt-I for indoor use, no question. Read and follow the label instructions and be sure that you don't add more watering cycles when you probably need to be reducing the frequency.

I agree with Rhizo completely. Use the BTi and be patient, it takes a while to break the breeding cycle, make sure all eggs laid have hatched and those resulting larvae eliminated. Use it each time you water, watering as needed and not on a set day or schedule, be consistent with the BTi and don't quit too soon, you'll use it about 3 weeks or so. I don't think I'd even bother with the stickey traps, the adults are only annoying not harmful, and happily they don't live but a few days. If the treated larvae aren't reaching adulthood, adults are soon resolved/gone.

If you do buy and use sticky traps, please limit their use to indoors. Outside, if you were tempted to apply them for something there, they can attract and kill small birds who notice the insects that have become stuck, become stuck themselves. i.e. chickadees

Understanding something about Fungus Gnats and their life cycles can be of a lot of help in controlling them and the link I have attached may of some help.
The Fungus Gnat larva need a moist environment of lots of organic matter to hatch and grow in so often simply cutting back on watering and allowing the top 2 to 3 inches of growing medium to dry out is enough. However, one could use some Bacillus thuringiensis - Israelensis, BtI, but that is a temporary solution while allowing the soil to dry out between watering is more long term.
I have not ever seen any reports of small birds getting stuck on yellow, blue, red, or any other color of sticky traps placed outside to monitor or trap insects. That may have come from reports of various species of birds getting stuck on glue traps, something different.

Here is a link that might be useful: About Fungus Gnats

Sticky traps are a hazard for other insects, as well as small frogs and the anole (and other) lizards very common to warm climate areas. Lacewings, parasitic wasps, small syrphids, mantids and other predators, bees, spiders, and others are very commonly a victim of yellow sticky traps.

They should never be recommended for outdoor use, Kimmsr. If you actually used them in your garden, you would soon see the 'interesting' results.

Kimmser, when I caution against using sticky traps outdoors its with reason. I did kill a small bird myself as a young gardener with a yellow trap, not an attempted pest control step I'm at all proud of. A wing was completely stuck to the yellow strip and the bird likely died of exhaustion or stress. You seem to be quick to question suggestions that are outside your own experience, I'm not sure why you would perceive that as helpful.

Allowing the soil surface to dry between waterings is the first remedy to try, and may well eliminate a fungus gnat problem. However, that was not an option for me this spring when a light infestation appeared in a terrarium. One application of granular Bti that I keep on hand for use in the small bog garden adjacent to my koi pond did the trick within 24 hours.

Many people find, too, that peat based potting mixes are attractive to fungus gnats, whether they are over watered or not. It is impossible to let the container dry to the point of keeping gnats away without killing the plant.

Changing to a different kind of medium, or simply amending can do the trick for most people.

morz8, if that was a real problem with those yellow sticky traps every horticulturist, entomologist, or bird expert would be campaigning to eliminate them from the garden. I have seen birds pick insects off the yellow sticky traps, but know no one that has seen a bird trapped by one, although I could imagine that if someone used something like Tanglefoot on one of these traps that might possibly happen.

Well, you do know someone....Me. And it was an unaltered approx. 2x8" sticky strip in yellow - unaltered out of the package in any way. Hanging in a viburnum if you want more details. Why would I make that up - it IS a threat to small birds, I've seen it.

This post was edited by morz8 on Mon, Aug 12, 13 at 16:47