Fungus gnats

Wed, 09 Nov 2005 12:33:33 PST
>I have a nightmarish fungus gnat infestation happening right now and I was hoping
>that using the granite grit straight would help to eliminate the gnats.

Hi Linda,  
Using granite grit may help in controlling the gnat problem by allowing the top portion of the container to dry out causing the eggs and larvae to desicate.  Still, that alone will not get them under control.  They have a life span of about 1 month, and all phases of the live span will be going on at the same time.  In other words, every day more will be hatching out.  Pyrethrins, Bacillus thuringiensis subsp. israelensis, predatory mites, and predatory nematodes are controls of choice. They work by different methods and on different parts of the life cycle.  What ever method is used, diligence in repeating the control is required, sometimes for many weeks. These things are a real pain to get rid of.


Gary in Hilo, HI

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