Answer: Control of the narcissus bulb fly is not easy. The insect has few natural enemies. Cultural controls include lifting the bulbs as soon as the tops die back and then sorting out and destroying infested bulbs should also help to decrease the population for the following year. Catching the flies in an insect net and destroying them should also help to decrease the population (each female destroyed means 100 potential maggots are destroyed). A hot water bath has also been found to be effective in killing maggots in infested bulbs. Maggots can be killed if bulbs are submerged in water kept at about 110 degrees for 40 minutes. Care must be taken to avoid overheating the bulbs even for a short time as the bulbs may be adversely affected by high temperatures. For chemical control, drench a mixture of insecticides and water in early May. For specific chemical control recommendations, see your Cooperative Extension publications on ornamental plant pest management.
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