Target Crops: Onions & Garlic.
Damage
When young onion plants wilt for no apparent reason, pull up a sample plant to check for legless worms (maggots) feeding on it roots. Plant may break off as you pull it from the ground.
Prevention
Floating row covers (fleece) are an effective way to prevent egg laying by adults. Be sure to get covers installed early, before the newly emerged adults fly in search of host plants.
Remove badly damaged plants, as the maggots can move from one plant to another.
Pest & Diseases Solution