Other states and territories would love to return to sender, but the QFF doesn’t cooperate. 

The Queensland Fruit Fly is so well known, the abbreviation is widely recognised as representing a threat to the wealth of growers of most fruits almost anywhere (in reality it is a native of central coastal Queensland, but very geographically ambitious).

PyBo natural pyrethrum concentrate is not something I can flog for its control; I have mentioned QFF in only a few of the many articles I’ve written for Tree Crop Magazine.

I wouldn’t have made even a dollar out of QFF control, so you might believe me when I say I’m here to help you and, I’m not even from the government.

My segment is titled Know Your Pest; and as QFF is a major pest, here goes…

It’s just a tiny, 7mm long fly. It’s soft, it has nice orange, yellow and brown colouring, it doesn’t sting or bite people.

You don’t even have to give the Aussie salute waving it away from your face – in fact you hardly notice them.

That’s part reason for their success.

Success?

Yep, there are a lot of committees in a lot of capital cities, lots more in fruit-growing communities, and all spending manpower and money to get you to co-operate and reduce the spread and the damage QFF cause.

If you do as we say, it will cost you money; if you don’t, it will keep costing you more money in fines, loss of reputation, maybe the cost of finding another crop to grow.

QFF facts of life…

The female lays it eggs by pushing its ovipositor (a hollow spike at the end its abdomen) into a developing fruit as soon as it detects a degree of ‘softness’ (meaning ‘very little’). One egg is laid at a time, and she can do this around 100 times a day.

Let’s stop right there.

If females are laying eggs, it’s because they were able to find a male with which to mate.

Your control program should have started weeks ago.

Egg laying is definitely preventable, and it is up to you.

So, now let’s begin at the beginning…

Divide and conquer is a long-established battle cry and/or strategy.

Now, separate your strategies into anti-male, anti-female, (which becomes an anti-egg strategy).

You are only responsible for what happens at your block but, having conversations with your neighbours and agreeing to do your combined utmost to keep males and females apart is the main game.

You really don’t want pregnant females flying in from next door… and neither do your neighbours.

First, take out the males before they find females.

They are suckers for sex but can’t tell the difference between the real thing and a fake pheromone.

Being very mobile and knowing the competition is also randy, they soon find what Bugs for Bugs call a MAT cup. Male Annihilation Technique cups are put in trees and nearby sheltered areas and there is a lethal kicker to ensure they never find true love. Works a treat.

Using almost the same principle, there is a way to entice females to their death.

Females have sucking mouthparts, and they desperately crave protein.

As any chef will tell you, eggs are mainly protein, so if the current QFF population is going to survive in your crop/neighbourhood, these faked love and foods are to be avoided.

Their problem is: they can’t help themselves.

Your job is to ‘sell these dreams’ to QFF all the year through.

It doesn’t much matter when you start because QFF can survive in winters of single digit temperatures as adults and probably as pupae in the soil after they’ve leglessly wriggled out of a piece of fruit.

The change from about 10mm maggot to 7mm adult takes place inside the last larval ‘skin’ which appears like an ovoid cocoon about 10mm long and is usually down in the soil a bit lower than birds (and hopefully ants) can find them.

Mid to late summer is when activity is most damaging, and the cycle is completed in 2-3 weeks, after which the adults can live for say two months. In winter that may be extended to maybe four months, but they are not very active – which also means they are not as interested in MAT cups or protein bait.

I didn’t think to write this article in winter to encourage you to start at petal-fall. Sorry, but as I said last paragraph it doesn’t much matter when you start, as long as you do, and you keep up the baiting – forever.

There is another control tool which you might consider: systemic insecticides.

Applied to the foliage of your crop, systemics enter the sap stream and the larvae inside the fruit die.

As always, ensure label directions must be followed, especially the withholding period.

One application may be enough, as long as you immediately follow up and get the baiting system in full swing before the systemics weaken.

Hygiene is a major contributor to control/elimination.

All infested fruit must be destroyed; dropped fruit and fruit that doesn’t pass the packing quality control standard.

No larvae must be allowed to escape to hide as pupae.

Destroyed.

How do you measure human success?

Monitoring.

Monitors have been used since I was a boy; you can tell by the number of bodies per week whether the QFF population is rising, falling or non-existent.

Escape clause: lack of activity by adults in winter may give you a nil reading because they just didn’t want to waste effort and leave their sheltered spot.

Ion Staunton is the entomologist at Pestech.com.au Manufacturers of Py-Bo Natural Pyrethrum Insecticidal Concentrate 1800 12345 7 And, thanks to Dan Papachek at Bugs for Bugs for Info.