Though the beetle larvae are pests for Raspberry growers, adults can be found feeding on pollen on a variety of wildflowers. The small adults often congregate within flowers, particularly composites such as Dandelion. (Source: RHS Gardening)
Byturus tomentosus lays its eggs on the flowers of Raspberries, Blackberries and Loganberries. When the larvae hatch they eat the developing fruit. The 4mm (about 1/8in) long adult beetles are pale brown and they lay eggs on the flowers in May to mid-July. The young larvae feed at the stalk end of the developing fruit, but later move inside to feed on the central plug. In late summer, the fully-fed larvae move into the soil where they overwinter as pupae.
Damaged ripe berries have greyish-brown dried up patches at the stalk end. A brownish-white grub, up to 8 mm long, may be found inside the fruits.
Byturus tomentosus monitoring can be achieved by using Russell IPM’s Raspberry beetle lure PH-158-1PR with either a Mothcatcher trap or a Ferolite trap.
The best way to track the presence of the the raspberry beetle is with the insect’s pheromone.
Russell IPM’s Ferolite water trap is the most effective to use for controlling the raspberry beetle. The traps can be used in conjunction with pheromone lures applied with Russell IPM’s Mothcatcher traps, to increase catch rate and enhance specificity.
1 Ferolite trap / 500 square meter.
Monitoring: 1-2 traps / ha for large plots, 3 traps for small plot
Control: 15-20 traps per hectare (To be confirmed by trials)
Insert pheromone lure in the plastic cage provided with the trap. Traps should be placed at the height of 15-30 cm above ground level. Fill the base of the trap with water and add one pack of trap enhancer or 10 gm of soap power. Pheromones can be added to cages found below the light source.
Collect data weekly from the start of the flight of the over wintering generation. During the height of the population more frequent reading may be needed. Decisions on pesticide application should not be taken solely on the trap catch data. Climatic and biological considerations should be taken in account.