|
The raspberry beetle and it's maggot - grub, is
probably the most destructive annoying pest of raspberries, blackberries
and loganberries. Many are not
found until the ripe raspberries undergo the ritual 'drowning' in cold
water before being prepared as puddings etc.
The adult beetles feed on the flowers, where they lay
their eggs. The young maggots than bore into the young fruit where they
feed until either picked or the fruit drops. The maggot then lives in
the ground - overwinters and emerges as the adult beetle, ready to begin
the life cycle again with either raspberries, blackberries or
loganberries as hosts.
Derris is still being suggested as a control on some
web sites and many books. We do not agree with this, as derris is now
withdrawn, and in any case cannot be used after September 2009. As
far as we are concerned, if it is bad enough to be withdrawn, then
responsible gardeners should not use it.
Bifenthrin can be used - a contact insecticide - on
Raspberries as the fruits first start to turn pink, on blackberries just
prior to flowers opening and on other hybrids, loganberries etc, spray
when the petals have fallen.
The image of the Raspberry beetle, it's larvae maggot
above is considerably larger than actual. |
