Bug FAQTurnip Maggot
Delia floralis · Order: Diptera · Family: Anthomyiidae
Turnip maggots are about 7 to 8 mm long, light gray with transparent yellowish wings veined in yellow. Their larvae feed on the roots of Brassicaceae plants, harming cabbage, turnip, radish, swede and related crops.
Source: Wikipedia
How to recognize it
The body is light gray and the wings are transparent yellowish with yellow veins.
Source: Wikipedia
Size
Adults are slightly larger than cabbage root flies, measuring about seven to eight millimetres long.
Source: Wikipedia
How to get rid of it
Control methods include early planting of strong plants, using peat-compost pots, adding extra fertilizer, deep autumn ploughing after harvest, and applying insecticides.
Source: Wikipedia
Where it lives
It is a worldwide pest of cultivated crops.
Source: Wikipedia
What it eats
The maggots feed on the roots of plants in the Brassicaceae family.
Source: Wikipedia
Life cycle
Usually only one generation develops each year.
Source: Wikipedia
When you see it
Pupae can survive temperatures down to to 33 °C and adults emerge when soil at pupal depth reaches about 18 °C.
Source: Wikipedia
Where it comes from
It occurs in North America as well as Western Europe, Russia, northeast China, Korea and Japan.
Source: Wikipedia
Lookalikes
It looks similar to the cabbage root fly but is a bit larger.
Source: Wikipedia
Where it is found in the US
Recorded in 2 of 51 states and DC. Most records: Alaska, New Mexico.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: introduced in Canada. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
How can I identify a turnip maggot?
Look for a light-gray fly about 7 to 8 mm long with transparent yellowish wings veined in yellow; it resembles a cabbage root fly but is slightly larger.
Source: Wikipedia
How many generations of turnip maggots occur each year?
Typically only one generation develops per year.
Source: Wikipedia
How can I control turnip maggots in my garden?
Plant strong crops early, use peat-compost pots, add extra fertilizer, deep-plough the soil in autumn after harvesting crucifers, and consider insecticide treatments.
Source: Wikipedia
Same family (Anthomyiidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Delia_floralis
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-23 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-23.