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Sciarid flies causes crop damage in three ways:

• The Sciara larvae - which cause the biggest problems - eat seedlings, transplanted plants and cuttings, causing damage to the crop. Especially the young crop suffers direct damage. However, this damage is usually localized since the young larvae hardly move at all. Damage manifests itself, for example, in growth retardation because nutrients cannot be absorbed properly, but in the worst case, plants die. High temperatures contribute to the constant reproduction of the insect, which lasts only 3-4 weeks. 
• They also cause cosmetic damage to crops because of their droppings. 
• Both the larvae as well as the adult scan spread various viruses and fungi such as Botrytis and Fusarium. 

Sciarid fly larvae can be recognized by their elongated and glassy body. They are about 3 to 4 mm in size. Adult sciarid flies are 2 to 3 cm in size and can be recognized by a V-marking on the tip of their wings. They also have a distinctive black head. Their body is black-brown with long legs. A sciarid fly lays its larvae in damp places between the roots of plants. The pest often occurs in the cultivated crops of potted plants but cut flowers including gerbera and lysianthus, are also affected by this pest.

​​​​Sciara larvae​​​​

​​​​Adult sciarid fly​​​​

The sciarid fly is often confused with the shore fly, but both insects cause different types of damage. A sciarid fly has a less sturdy build than a shore fly and has longer antennae. In addition, a shore fly often only causes cosmetic damage; it does not eat the crop.

Sciarid flies are common in high humidity and high temperatures. On average, the females lay 100 eggs a day and a newly hatched female sciarid fly can lay eggs after just a few hours. It is therefore important to combat sciarid flies as soon as possible. This can be done with the help of various natural enemies and chemical agents. Read more below.

The sciarid fly can be treated with nematodes and predatory beetles:

• After being distributed, the Steinernema feltiae nematodes actively seek out their prey and enter them after which they secrete bacteria that kill the prey. 
• The Atheta coriaria predatory beetle does not harm crops and can be used in almost any crops that are not too dry. 
• The Hypoaspis predatory soil mite especially settles in places where it can find plenty of food. Many different soil organisms are on the menu, so this predatory mite can survive almost all cultivated crops.

The sciarid fly is best treated in the final stage. Due to its rapid lifecycle, it is important to spray quickly in succession.

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