Pest profile

Apple Maggot

Rhagoletis pomonella · Diptera: Tephritidae[3]

The apple maggot is the most important insect pest of Minnesota-grown apples; its larvae riddle the fruit with brown, rotting trails.[2][1]

Adult apple maggot fly with dark-banded wings and a white spot on its back, resting on an apple
Adult apple maggot fly with dark-banded wings and a white spot on its back, resting on an apple. (c) Bex Goreham, some rights reserved (CC BY) — via iNaturalist, CC BY 4.0

How to identify it

  • Adults are about 1/5 to 1/4 inch long with clear, black-banded wings and an obvious white spot at the rear of the thorax.[1][2]
  • Females have four pale bands across the abdomen and males three.[1][2]
  • Larvae are cream colored, up to 1/4 inch, blunt at the rear and tapered to two black mouthhooks.[1]

Look-alikes

Look-alikeHow to tell them apart
Vinegar fliesSmall drosophilid flies are also called fruit flies but are much smaller than apple maggot flies.[1]
Codling moth larvaeCodling moth larvae are much larger than the rarely seen apple maggot larvae.[2]

Where it lives

It attacks apple, hawthorn and occasionally other Rosaceae. In California it's found from Sonoma County north, and moving home-grown apples into several southern counties is illegal.[1]

US map: public records from 23 states since 1990 (GBIF).

Biology and life cycle

Pupae overwinter in the soil, and adults emerge from late June through August, peaking in July.[1][2]

Newly emerged flies must feed on honeydew before they mate.[1]

A female lays about 300 eggs under apple skins over a 30-day life and marks each fruit to deter other females.[1]

Larvae feed three to four weeks, leave the fruit and pupate in soil; there's usually one generation a year.[1][2]

Damage and signs

  • Egg-laying sites become dark decayed spots on soft apples or dimples on hard ones, and fruit turns pitted and misshapen.[1][2]
  • Larvae tunnel through the flesh, leaving brown trails, and rot follows until fruit drops.[1][2]

Health risk

It damages fruit only; neither source mentions any risk to people.[1][2]

Control

Keep them out

Bag each apple in a sandwich bag with snipped corners after thinning, in early to mid-June.[2]

Sanitation

Pick up fallen apples often during the season and after harvest, and send them away in sealed bags rather than composting them at home.[2][1]

Traps and physical control

Hang bright red sticky spheres at least 3 inches across on the outer canopy to catch egg-laying females; mind birds, which can get stuck.[2][1]

Pesticides

Where it's been a problem, UC IPM suggests spinosad, ideally premixed with a fruit fly bait, once yellow sticky traps catch the first flies.[1]

Common questions

Why are my apples full of brown trails?
Apple maggot larvae tunnel through the flesh and leave brown, rotting trails.[1][2]
Does bagging apples really work?
Yes. Bagging each apple in early to mid-June protects it from apple maggot for the rest of the season.[2]
I found it in Southern California. What now?
Report suspected apple maggots in Central or Southern California to the County Agricultural Commissioner.[1]

Sources

  1. University of California Statewide IPM Program, “Apple Maggot (Pests in Gardens and Landscapes).” ipm.ucanr.edu/PMG/GARDEN/FRUIT/PESTS/applemaggot.html (accessed 2026-10-06)
  2. University of Minnesota Extension, “Apple maggot (Yard and garden insects).” extension.umn.edu/yard-and-garden-insects/apple-maggot (accessed 2026-10-06)
  3. iNaturalist, “Rhagoletis pomonella taxon page (order and family).” www.inaturalist.org/taxa/366909 (accessed 2026-10-06)

Updated 2026-10-14. Built from sourced records. Spot an error? Tell us.