What's eating my plum 'stanley'?

Stanley plum shares the pest profile of other Prunus domestica varieties. Plum moth larvae infest ripe fruit in August–September. Black bean aphid colonies appear on shoot tips in spring. Plum sawfly can destroy fruitlets. In North America, plum curculio is a serious pest. Pheromone traps and early season monitoring are essential.

Maggots found inside ripe Stanley plums around the stone; frass visible at the stalk end; premature fruit drop in heavy infestations Pheromone traps from late May; remove all fallen fruit promptly; pyrethrin sprays offer limited control but can reduce adult populations near harvest

Dense black colonies on shoot tips and undersides of leaves from April; shoot tips curl and growth is stunted Pinch out heavily infested shoot tips; spray with insecticidal soap; encourage natural enemies; plant-oil winter wash to destroy overwintering eggs in bark

Fruitlets holed and drop prematurely in late May–June; pale larva with brown head found inside tunnelling around the stone Spray pyrethrin within 7–10 days of petal fall; collect and destroy all dropped fruitlets to break the life cycle

Crescent-shaped egg-laying scars on young fruit; grubs tunnel inside causing early drop; adults also feed on buds and flowers Kaolin clay barrier spray from petal fall through fruit development; pyrethrin or spinosad sprays at shuck-fall; collect and destroy all dropped fruit