5. Good Organic Gardening - September-October 2016 AvxHome.in

PEST PATROL | Queensland fruit fly
Hygiene
Don’t leave fruit on your trees or
vegetables in the garden until they are
over-mature as these conditions are
ideal for QFF to lay in. Pick up any fallen
fruit or vegetables that are no good,
put them in a sealed bag and dispose
of them in the bin. Don’t compost them,
as you are only promoting a suitable
source for QFF to lay in.
Beautifully netted fruit trees at Royal Mail
Hotel kitchen garden in Dunkeld, Victoria
have been the most effective control for
commercial fruit growers, these chemicals
also killed beneficial insects that assist in
controlling insect pests and so those pests
began to be hard to control. Many of these
chemicals are no longer available for use.
Other techniques to control QFF have been
developed by proactive horticulturists and
fruit growers and have been in use by some
growers for 15 years. These are not harmful to
beneficial insects so they can now be used in
the home gardening sector.
The main control methods that will make
the battle with QFF easier for the home
gardener include the following:
Full exclusion netting
Permanent structures or drape nets are
the most successful control measures. It’s
important that these nets be secured to the
ground to prevent QFF getting underneath
the netting. This should be in place before
fruit and vegetables are half mature as QFF
will sometimes sting fruit and vegetables
when they are still hard. They may not
lay eggs at this time, but they will leave a
pin-sized mark on the skin that will cause
a deformity, or the fruit or vegetable may
drop off as it grows.
Baiting
Protein baits that attract both male and female
fruit flies are applied to the lower foliage of
plants and should also be used to bait the
perimeter of your house block. Bait can be
applied to any type of tree or shrub. This
control measure should be used in conjunction
with trapping male flies with female fruit fly
pheromone attractant baits hung in traps.
This process reduces the number of male flies
available to mate with female flies.
The whole process must begin in late
winter to keep the numbers of flies down
as they emerge with the warming spring
weather. Please note that control measures
of this type are difficult if your neighbours’
untreated crops are hosts for QFF; hence
even more reason to bait the perimeter of
your own yard so flies will feed there first
before moving to your fruit and vegetables.
Queensland fruit fly maggots
For home gardeners
who have no experience
in identifying this pest,
by the time they realise
they have damage it’s
very often too late.
Fine mesh bags
These can be purchased and tied around
fruit and vegetables but they’re timeconsuming
to apply and therefore not really
a good option for large numbers of fruit or
vegetables. Unless vented, the plastic bags
available for bagging create humidity and
have been known to promote fungal diseases
as the fruit or vegetable matures. Bags need
to be clear so sunlight can penetrate to the
fruit or vegetable skin to give good colour and
therefore good flavour.
Timing
QFF is most active from early spring through
to late autumn.
Fruit fly trap
• For more information on fruit-fly control
techniques and products consult PlantNet at
plantnet.com.au
Home remedies/
attractants
Please be aware there are many home
remedies suggested for the control of
QFF. It’s important that you learn to
identify what QFF looks like as many of
the suggested catch-and-kill remedies
actually don’t attract QFF but do attract
other insects and flies, leaving your
crops vulnerable to damage by QFF.
Kerry Boyne, Mark Dann, Jana Holmer
56 | Good Organic Gardening