• Fungus Gnat Flies

    Fungus Gnat
  • Fungus Gnat
  • Fungus Gnat


Since firewood and house plants are the two main sources of infestation, it’s a good idea to apply a preventative treatment of Maheu&Maheu Insecticide Dust to firewood as soon as it is brought into the house in the fall. This eliminates fungus gnats and a number of other undesirable insects living in the wood or in cracks in the logs. As for house plants, treat the surface of the potting soil with Maheu&Maheu Insecticide Dust , containing pyrethrins and diatomaceous earth. To get rid of adults, you can use pyrethrin-based Maheu&Maheu Flying Insect Killer to treat areas where fungus gnats gather, near windows for example


  • Cut back on plant watering
  • Put sticky traps in plants to catch flies
  • Use insecticide dust on plant soil surface and on firewood if necessary


  • Avoid overwatering plants
  • Apply diatomaceous earth–based insecticide dust when stacking firewood indoors

Description and development

Members of the fungus gnat family (Sciaridae ) are holometabolous insects (having four very different life stages) in the Diptera order. The adult measures less than 5 mm and is gray or black. Fungus gnats are distinctive in that their eyes meet above the base of the antennae. They can also be recognized by the pattern of the veins in the wings.
Fungus gnats have four distinct stages in their life cycle: egg, larva, pupa, and adult. The larva feeds on fungi, decomposing plants, or plant roots. The female chooses where she lays her eggs based on the availability of food sources for the larvae. House plants and firewood are the most common sources of fungus gnat infestations in homes.


The adults are the main problem indoors. Since they are attracted to light, they are usually found on window frames. Live fungus gnats keep their wings folded on the body, whereas dead fungus gnats have their wings spread. They are generally quite numerous.


An additional tip: Avoid watering house plants too much—that encourages fungus gnats!

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