What's eating my marjorie's seedling plum?

Marjorie's Seedling, a late-cropping plum, is attacked by plum moth, plum sawfly, brown scale on older branches, and slug-like plum sawfly larvae. Its late harvest window also exposes ripe fruit to wasps. Plum moth causes the most consistent damage — pheromone traps and timely spinosad applications are the primary defence.

Larvae tunnel to the stone, leaving frass-contaminated flesh; fruit drops before fully ripe or reveals a caterpillar at picking. Pheromone traps from May; spinosad applied at first adult catch and again three weeks later; collect and destroy windfalls weekly.

Larvae bore into very young fruitlets just after petal fall, exuding gummy sap at the entry point; fruitlets drop in May–June. Pyrethrin or deltamethrin spray at petal fall; remove infested fruitlets to reduce next season's population.

Waxy brown scales encrust older branches, sucking sap and producing honeydew that leads to sooty mould. Scrub off with a soft brush; apply plant oil-based winter wash to bark when dormant to smother overwintering scales.

Excavates late-ripening fruit flesh, especially where skin is split or punctured; greatly increases yield loss near harvest. Set wasp traps around the tree; harvest promptly as fruit ripens; pick up windfalls daily.