The Queensland Fruit Fly (Dacus Tryoni) and the Mediterranean Fruit Fly (Cerititis Capitata) are significant pests of a wide range of fruits and fruits that generally get called vegetables (tomatoes, capsicums, chillies, eggplant). If you live in an area affected by these pests, as we do, you have our sympathy because they can really cause havoc with the affected crops, there is nothing like cutting open a beautiful ripe tomato and finding it full of maggots! One home grown way of reducing the effect of their predations is to install fruit fly traps in the areas where you are growing fruits and vegetables likely to be affected.
To make the traps you will need a 1.25 litre or 2 litre PET soft drink bottle, a hobby knife or pair of scissors, some electrical tape, preferably red or yellow, some wire or string and an attractant/poison which will be discussed later.
Making the trap
Take the PET drink bottle and cut the top off about 1 centimetre down from where the shoulder meets the body of the bottle.
Now invert the funnel shaped piece of plastic formed by this operation and insert it in the open end of the cut away bottle.
Secure the funnel by placing red or yellow (or both) plastic take around the end of the bottle/funnel set up. Flying insects are attracted to red and yellow which is why these colours are used.
Cut, drill or pierce two small holes, one on each side of the top and thread some wire or string through to hang the trap on the tree with.
Pour the attractant/poison mix into the bottle and hang in the tree.
Inspect the trap regularly to see how successful you are and empty and replace the attractant every three weeks, the attractant and dead flies can go into the compost.
The trap works by attracting the flies then sticking them up or poisoning them and either way making it difficult to get out of the bottle again. You can either make up the attractant into a sticky paste or add a poison that will finish the flies off once they contact or feed on the attractant mix.
Attractants may include – molasses, fruit juice, vanilla essence, jam, vegemite, ammonia
Pesticides that could be use include – borax, pyrethrum or derris dust
