# My Plant Has Gnats
Plants are susceptible to a variety of insects, including fungus gnats. Although adults do not cause much damage, their larvae feed on plant roots to diminish vigor and vitality. With a single female laying 100 to 200 eggs, a few gnats quickly turn into a large infestation unless remedied. Take steps to treat gnats immediately before the problem gets out of hand.
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Identification
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Fungus gnats are members of the fly family that resemble mosquitoes. Ranging in size from 1/10 to 1/8 inch, the pests appear in shades of grayish black or yellowish-orange. Gnats are weak fliers and often a source of distraction. The eggs are tiny, oval and smooth. Gnat larvae have white legless bodies, black heads and measure 1/4 inch when mature. Gnat problems are at their worst during the spring and winter.
Damage
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Gnats develop in moist and shaded decaying organic matter in indoor and outdoor plants. They are most common in indoor environments because the peat to soil ratio is formulated to retain moisture instead of improving drainage. The moisture buildup in the soil creates an ideal environment conducive to breeding the pests. The larvae damage plant root systems, causing stunted plant growth and increasing chances of disease-spreading organisms penetrating root wounds. The larvae are particularly damaging to the roots of young plants and seedlings. Infested young plants exhibit signs of declined health because they cannot tolerate root wounds.
Cultural Control
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Avoid overwatering your plants to reduce the occurrence of these critters. When irrigating your potted plant, allow excess water to drain out through the holes at its base. Allow the soil surface to dry out lightly before you irrigate again. However, avoid drying the soil to the extent of causing the plant to wilt or dehydrate. Remove dead matter, mulch and compost from around the plants, as these serve as ideal breeding areas for the gnats. Rake or collect fallen leaves and clippings from around the plant and discard.
Insecticide
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Adult gnats are easily killed with pyrethrin sprays specifically formulated for use against gnats. However, the chemical treatments provide short-term control against the flying critters, since more gnats are likely to appear once the chemicals in the insecticide dissipate. Biological insecticides containing Bacillus thuringiensis var. israelensis kill the larvae, thereby preventing future outbreaks. The insecticide is applied as soil drenches to potted plants. Follow label directions for dosage recommendations when applying the soil drench.
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