Plum fruit moth
Aspila funebrana
Appearance
The adult plum fruit moths are about 8 mm long and have a wingspan of 11–15 mm. The forewings are dull violet to grey in colour, with a dark comma-shaped mark at the wing tips, whilst the hindwings are almost uniformly grey-brown. Plum fruit moth butterflies can be confused with butterflies of other moth species (e.g. the peach fruit moth, Aspila molesta). Accurate identification can only be carried out in the laboratory using microscopic specimens or molecular genetic analysis.
The eggs of the plum fruit moth are flat-oval (hourglass-shaped) with a diameter of approx. 0.7 mm and are initially translucent. During embryonic development, the eggs first turn milky white, with an orange-reddish ring. Finally, the black-headed stage emerges.
The caterpillars hatching from these are initially whitish and subsequently turn reddish with a dark-coloured head. The caterpillars grow to about 10–12 mm in length, are sparsely hairy and have 16 legs. The plum fruit moth has five caterpillar stages.
The pupal stage is 6–7 mm long, light brown in colour and spun into a cocoon.
© Tomislav Jemrić, University of Zagreb, Faculty of Agriculture, Department of Pomology, Zagreb, Croatia
Biology
The plum moth can develop three partly overlapping generations per year. Hibernation largely takes place in the caterpillar stage in cracks or in bark scales on the trunk or crevices in the soil. Pupation does not occur until the following spring, when temperatures reach 10 °C or higher. The hatching of the crepuscular moths from the pupae takes place a few weeks after petal fall (from about the end of April).
The females lay 40-80 eggs singly or in small groups on the underside of young, unripe fruit from temperatures above 12 °C, mainly in the evening. After one to two weeks, the caterpillars hatch (1st larval stage) and bore into the fruit, where they feed on the flesh for about three to five weeks until the end of the caterpillar stage (5th larval stage). Usually only one caterpillar develops per fruit. The adult caterpillars of the first generation leave the fruit and pupate in a cocoon on the trunk or in the soil. The larger part of these individuals develops within one to four weeks into the moths of the second generation whose hatching begins around June. The other part of the pupated animals of the first generation, however, already goes into diapause in summer and hibernates. In climatically favorable regions, a third generation may emerge around mid-August, before the adult caterpillars of the last generation visit the overwintering sites.
Damage symptoms
From holes in infested fruits (borehole of the young caterpillar) drop-shaped gum flow emerges. Infestation by the first plum moth generation also shows premature bluish-purple discoloration of young fruits, which drop off as early as June and July. This symptom is often confused with natural fruit drop. Infestation by the second generation later in the year results in prematurely ripe fruit (distress ripening).
Inside the infested fruit, the pulp is destroyed and fecal crumbs are found as well as the caterpillar (plum maggot).
Host plants
The main host plants of the plum moth are cultivated and wild plums(Prunus domestica), plums(Prunus dom estica subsp. domestica) and apricots(Prunus armeniaca). In addition, peach(Prunus persica), sloe(Prunus spinosa), bird cherry (Prunusavium) and almond(Prunus dulcis) are also attacked.
Prevention and control
- Choice of variety: Late-ripening varieties suffer more damage. Early-ripening varieties should therefore be grown.
- In home gardens and allotments, fruit infested by the plum fruit moth (fallen fruit) can be collected regularly and destroyed before the larvae bore their way out and migrate to pupate (collecting the fruit using a tarpaulin or net can be helpful; shaking the tree may assist; do not compost the fruit).
- To combat overwintering caterpillars, strips of corrugated cardboard (in which the caterpillars spin their cocoons to overwinter) can be attached to the trunks from July onwards, removed before pupation is complete, and destroyed along with the caterpillars inside.
- Pheromones can be used as part of confusion techniques to control the plum fruit moth.
- Possible dates for biological and chemical control measures: see the Plant Health Alert Service.
- Plant protection products for controlling the plum fruit moth are listed in the register of plant protection products authorised in Austria.
Last updated: 16.03.2026
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