If I am using a 2 gln watering can and put in 1/4 chunk of Dunk is that enough and do I have to let it sit over night before using it. Thank you
p.s. anyone know where to buy something easier?
What are you attempting to control? Dunks are usually just placed in the body of water you are intending to control the mosquito larvae in.
Sorry, I forgot to mention I am wanting to use this to control gnats in the plant soil of my outdoor containers. I read that you use Bacillus. I'm sure these are not shore flys but fungus gnats that came in a plant I ordered thru a catalogue compnay :(
Phoebe, I use about a quarter size chunk of dunk...hey I like the way that sounds... in a 2 gallon bucket. After It's been in there overnight or for a few hours, I pour about 2 quarts in a watering can, but leave the chunk in the bucket. Then I add more water to the bucket. This way the Bacillus lasts for a long time. I have been using this indoors for fungus gnats and it has been very effective. It did take a few days though. Also, keep using it for a little while after the gnats are gone to be sure you get all the larvae. Lisa
Dunks are for skeeters
Gnatrol is a Bt made for fungus gnats
Bacillus thuringiensis israelensis is the same active ingredient in Gnatrol and mosquito dunks. For heavy fungus gnat infestations you may need to re-apply two or three times at 5 day intervals. Bt only targets the immature stages and the adults live around 3 weeks. The best solution though is non-chemical: keep the soil as dry as horticulturally possible with infrequent, deep watering if the plants can stand it.
"The best solution though is non-chemical"
Bt is non-chemical. Your point on cultural methods is valid, however.
It's probably a matter of semantics and gets into a gray area where people have isolated and identified the active ingredient from a natural source. The delta endotoxin is naturally produced from a bacterial source. I also consider Spinosad (derived from another bacterial soil dweller) to be chemical, though it too naturally-derived. I don't think that there's much debate about rotenone, pyrethrum, or nicotine as being chemicals despite their natural origin.