Ichneumon wasps
Strawberries can be infested by many different aphid species, including potato, cucumber and peach aphids. Farmers deploy ichneumon wasps against these pests as a preventive measure. Ichneumon wasps can be released regularly in small cardboard cylinders. The wasps are highly host-specific. In other words, they specialise in a single type of aphid. Since several species of aphid are generally found at one and the same time, these beneficial insects are generally employed in mixtures.
The predatory gall midge can be deployed through repeated applications. When the first aphids appear, large quantities of ichneumon wasps or green lacewing larvae must be brought in immediately to control the pests. Green lacewing larvae are particularly suitable for treating outbreaks of colony-forming aphids. Ichneumon wasps, by contrast, display good foraging behaviour and track down individual aphids. A combination of these beneficial insects thus constitutes the optimum solution.