Adult fungus gnats have a few key features which make them easy to identify.
They are small, black flying insects with long legs and resemble tiny mosquitos in body type. They have clear or grey wings in a long oval shape, with a Y-shaped pattern in the centre. Gnats are about 2.5mm in size, and they are speedy flyers – good luck trying to catch one (little own 100).
Adult fungus gnats live for about a week before completing their life cycle. During that time, they can fly long distances apart, the length of which has never been investigated. However, I’ve seen them move from one side of a small house to another (about 30 meters), so lookout.
I’d like to point out fungus gnats aren’t harmful to humans.
Fungus gnats aim to lay eggs in nutrient-rich soil, providing their larvae with the best chance of life. But unfortunately, their ‘nutrients’ is plant matter, which means large roots, hair roots, and decaying matter (dead leaves), are their favourite meal.
They will fly from plant to plant and deposit their eggs in soil with sufficient moisture.
Fungus gnat larvae are little, transparent, legless grubs with unique shiny blackheads. They eat plant roots to grow before they pupate and become flying adult fungus gnats.
They eat plant roots for a week before transforming, creating sufficient damage. If numerous fungus gnat larvae eat the roots of one plant, it won’t survive for long.