Controls

Integrated Pest Management

Queensland Fruit Fly controls are most effective when an Integrated Pest Management (IPM) process is applied. The lifecycle of the pest is studied and the weaknesses where controls can be applied are observed and acted upon. There is a focus on using and balancing all of the cultural, biological and chemical controls to achieve pest management or best practice. In the case of the QFF, the young flies are most susceptible to protein bait, the juvenile male is attracted to para pheromones (used in traps and M.A.T.), the virgin females are most attracted to protein bait and protein traps, while the pregnant female QFF are likely to be attracted to fruit scented traps. Cultural techniques include physical barriers (netting) and good hygiene practices like harvesting fruit before it falls, preventing QFF in the area, and correct fruit disposal if infested with QFF.

QFF in biotrap sticky card B KOLL

AREA WIDE MANAGEMENT requires everyone in a region to be involved and active in managing fruit fly.

Area Wide Management

To reduce Queensland Fruit Fly population in an area, QFF controls need to be applied across a whole region, by everyone in that region.

This means you, your neighbours, owners, tenants, volunteers, managers, organisations and public land managers all working together to reduce QFF risk, remove unmanaged QFF host plants and treat QFF infestations using best practice management tools from the toolbox.

For support in applying area wide management in your community, visit Hort Frontiers Fruit Fly Fund AWM Guidelines.

QFF Management Tool Box

The tools in the QFF management toolbox allow for a suite of actions to be taken to deliver a multi-pronged approach for managing QFF populations and incursions or outbreaks.

The QFF TOOLBOX has tools to use for monitoring, prevention and control.

  • Hygiene
  • Traps
  • M.A.T.
  • Bait
  • Netting
  • Cover Sprays

Some tools are best used by gardeners, and others are more appropriate for commercial fruit production and a combination could be used in public land management settings. It is important that the solutions work for you and contribute to the Area Wide Management of QFF.

QFF in biotrap sticky card

TRAPS – an indicator tool

Monitoring the Queensland Fruit Fly population with fruit fly traps helps land managers make decisions for QFF prevention and timely control actions. QFF traps are best used as part of the whole suite of fruit fly management tools, and as part of an Area Wide Management approach to controlling fruit fly. Traps alone do not control QFF.

  • Ensure QFF monitoring traps are installed and the lures are current. Always remove expired or inactive traps form the field.
  • Check traps at least weekly, or more often if possible. An unchecked trap can lead to misinformation and lack of action.
  • Record any QFF caught in traps and notify the Regional Co-ordinator or local Agronomist to promote Area Wide Management from other land managers. Traps can indicate if QFF are increasing and more actions from the QFF management tool box need to be taken, or they can indicate if controls are being effective.
  • Fruit checks are an essential monitoring action to compliment trapping.

TRAPS – types of traps and lures

There are many brands and designs of fruit fly traps. There are three main attractants or lures used, male attractants, protein/food scents, and mimicking of fruit. It is good to use a variety of fruit fly trap styles to help get a picture of what type of QFF are around at any time.

A male QFF attractant

MALE QFF traps use a para pheromone attractant (Cue-lure) to attract the male QFF. He needs this to then later make his own female QFF attracting pheromones. The more para pheromone that the male QFF accumulates, the more attractive he can be. Once he has sufficient, he no longer actively seeks out Cue-lure in the wild or the traps, and he concentrates on mating activities. Hence, these traps don’t catch all the male QFF that are around, what is caught is only a sample of the population size. Some lures are soaked into a pad or a wax block, some are liquid based.

For the most success, start with male QFF traps early in the fruit season. Male lures can attract QFF from about 200m away. They work best in a 400m x 400m grid pattern over a wide area. QFF management actions should be elevated if one fly is found in the trap, increasing in intensity if more flies continue to be found.

A food (protein) attractant

FOOD or PROTEIN based traps contain a protein food to attractant QFF. Hungry ‘teenage’ QFF and virgin female QFF are the most frequent visitors to protein-based traps because they each have a high protein requirement to their diet. Occasionally, other non-target flies are attracted to these lures because of the decaying organic matter scents. Some commercially available protein attractants are gels, some are liquids.

Home gardeners can make their own trap with a recycled bottle using common kitchen ingredients to make their own protein and fruit lure. For the most success, install protein based traps before female QFF mate.  Protein lures can only attract QFF from about 15-20m away. They work best installed in each tree or in high-risk areas to compliment the male QFF trapping grids.

A fruit attractant

FRUIT mimicking traps use the scent of ripe fruit along with colour and shape similar to ripe fruit to attract pregnant ‘egg laying’ female QFF. They are effective from about 20 metres away. Commercially available or home gardeners can make their own trap and use common kitchen ingredients to make a fruit juice lure.

TRAPS – types of kill mechanisms

INSECTICIDE traps have an active insecticide soaked into the wick/mallet or block that contains the lure, or an insecticide cube that can be added to any of the attractants.

STICKY traps have a replaceable card covered with a very sticky layer. This must be contained inside the trap to avoid it harming wildlife. Sticky cards are easy for viewing and photographing when seeking assistance with identification and counting flies. They are also insecticide free and fit well into organic production systems.

DROWNING based traps have a liquid that drowns the insect entering the trap. The liquid level needs to be kept topped up in summer and checked regularly in rainy conditions to prevent it overflowing. Most liquids have an additive like dishwashing liquid to reduce surface tension on the top of the liquid and increase the chance of the visiting insect drowning.

TRAPS – how to install a trap

  1. Place your trap in a tree at about 1.5m high
  2. Choose a well-ventilated warm spot in the tree, in amongst the foliage, out of direct sunlight.
  3. Check traps at least weekly during the growing season. Place in a spot you visit often and can observe easily. Keep weekly records.
  4. Maintain traps with fresh lures and QFF killing mechanisms frequently (about 8-12 weeks).  Always follow the label instructions on the trap.
  5. Place traps at least 30m away from other lures and attractants. Make a property map to plan the trap deployments and their effective range.
  6. Use a variety of trap lures to monitor different parts of the QFF population
  7. Keep traps and lures away from children and animals
  8. Be part of a bigger monitoring program. Encourage your neighbours and community groups to also monitor for QFF, sharing the trap finds with each other.
QFF in biotrap sticky card

BAIT – a control tool

Queensland Fruit Fly bait is a protein food source that attracts and kills QFF. An insecticide is mixed with the food-based bait becoming lethal to QFF when in contact or consumed. Synthetic and organic insecticides are toxicant options. Bait programs are very effective because hungry QFF seek out the treatment, rather than you trying to find and reach the QFF with a broad-spectrum insecticide. Because the bait droplets do not attract beneficial pollination insects, the negative impact on non-target species is kept to a minimum.

Residential gardeners will likely find ready-to-go bait (with organic insecticide already added) in garden centres and nurseries (just add water). Commercial fruit growers can buy a bulk bait supply of the same ready-to go-product, or a bulk protein bait only product with the option of adding an approved insecticide, possibly already in the farm inventory.

BAIT – when to start

Apply bait to attract and kill QFF in the immediate area as soon as traps indicate QFF are active (use data from your traps, the area wide surveillance grid traps, or the neighbour’s traps). Start earlier if you’re in a high-risk situation (use as a preventative option), or if there are other host crops preceding your crop harvest. This could mean starting 6-8 weeks prior to harvest. The QFF baiting technique works better if your neighbours are also baiting.

BAIT – how to apply

Make up a fresh bait mixture in the tank each time. Tank size and application method will vary according to the size of the area needing coverage (handheld pump packs or motorised pressure pumps, small tanks on ATV’s or large tanks on tractors or trailers). Measure the total volume of bait needed for your area using the rates advised on the label. Bait mixture needs agitation in the tank to blend well and avoid lumps blocking nozzles.

Apply the bait to the target area using a continuous focused stream via a dedicated nozzle(s), whilst moving. Aim to apply small droplets of bait onto leaves of trees & shrubs at 1-1.5m high – avoiding fruit. Refer to the label directions for your crop, your situation, and your chosen products.

  • Remember to bait the house garden, fence lines, farm sheds & chicken sheds, around fruit disposal areas, and weedy areas with unmanaged host fruit risk.
  • Low to the ground crops or fruit that can’t be washed aren’t very suitable for in-crop baiting applications. Try creating bait stations on trellis posts or apply bait to catch crops planted specifically. Use areas where the fruit harvest is completed as baiting blocks.
  • Thickeners and sweeteners can be added to improve attraction to QFF and increase baiting efficacy. 

BAIT – a baiting program

Apply bait regularly (at least weekly) and reapply bait after rainfall or overhead irrigation (as per label directions). Adjust application days around the weather forecast. Use more frequent applications in high pressure situations.

Continue your baiting program until fruit fly pressure reduces (refer to traps and monitoring results). Post harvest baiting is important to protect the next crops to mature and to reduce the QFF population from year to year. Cooler climate areas like the Yarra Valley can mean late season QFF larvae take longer to pupate, and they may not emerge from the ground for 2-3 weeks. This means that protein bait needs to be available post harvest for enough time to target the emerging flies of the next QFF generation.

Best results are achieved when bait is applied over a wide area e.g. a neighbourhood or several fruit orchards and in conjunction with other QFF controls. Isolated fruit growing areas have reported successes with some M.A.T. and a strict bait routine started early.

QFF in biotrap sticky card

PRODUCTION AREA HYGIENE – a control tool

Pick fruit before it falls. Preventing the lifecycle from being able to continue is key to QFF management. If the fruit is infested, then timely harvest and containment is the sure way to treat QFF chemically free.

Cleaning up fallen fruit is important to prevent the scent of ripe fruit attracting QFF from other areas to your production area. Fruit will always fall, during harvest or if it’s windy. If there is still QFF larvae in fruit on the ground, QFF survival is reduced when the picked up fruit is treated and removed.

Prevent QFF entry into area/region/farm/garden. By controlling the fruit that comes into your production area it reduces the risk to your crop. Have a receival area, with treatment and disposal options at the ready.

Destroy suspect infested fruit with boiling, freezing or solarising.

Mulching fallen fruit is another option to reduce QFF risk, even if the fallen fruit has been managed well during the season. If fallen fruit is infested, mulching can reduce the survival rate of the larvae. Tractor wheels crushing fruit can also assist fruit destruction and desiccation.

Other hygiene tips:

  • Only grow what you need and can consume or cook yourself, as over production is less likely to get harvested and more likely to get infested.
  • Keep trees to a manageable height with training and pruning to make both netting and harvest easier.
  • Help pick your neighbour’s ripe fruit if need be and visa versa if you are absent for a period of time

Carefully design your production area to be able to net areas/plants in fruit, and allow other plants to be pollinated unaffected by QFF netting

QFF in biotrap sticky card

NETTING – a prevention tool

Queensland Fruit Flies are attracted to fruit for the purpose of laying eggs. Exclusion netting can be installed to protect the ripening fruit, preventing the pregnant female fly from accessing the fruit. Netting is an insecticide free method of protecting your fruit harvest.

Netting needs to be insect mesh with hole sizes about 2mm x 2mm (ideal for draping). Some netting is 1 x 3mm and can be used when stretched taught and fixed onto a permanent structure. Netting can be bought in wide lengths off the roll, in pre-cut fabric packs, or pre-sewn into box nets. Look for UV stabilised products for longevity. Cable ties make securing netting over unusual shapes a breeze.

Place netting on the crop requiring protection after pollination is complete, when fruitlets are small, green and hard. Make sure all nets are on before fruit starts to increase in size and change colour. It’s important to plan your garden so that fruit that needs pollination is not affected by the netting of other varieties.

All netting needs to be kept off the fruit. If fruit is touching the net, QFF can ‘sting’ (lay eggs into the fruit skin) from the outside of the net. A good system is to use poly pipe arches on upright supports like star pickets. The netting slides over them easily in install and pack up. If using a structure or a drape method, ensure the netting is sealed at the bottom to prevent QFF sneaking in.

Move the net between crops, as one finishes, and another starts. After harvest, take twigs and leaves out, repair holes and wash. Store in a bag or tub until next season. Mostly, netting is used by the home gardener as a technique to protect the fruit. Commercial producers find netting tricky to operate with, and difficult to afford over large areas.

QFF in biotrap sticky card

MALE ANNIHILATION TECHNIQUE (M.A.T.) – a control tool

Queensland Fruit Fly can be managed as a whole population by reducing the number of males available to breed early in the season, causing population decline.

Male Annihilation Technique (M.A.T.) involves deploying several insecticide and Cue-lure soaked devices (wicks/mallets/blocks/slow release putty) into trees at 1-1.5m high in a grid pattern over a wide area to attract and kill as many male QFF as possible. Insecticide is not applied to the fruit when using M.A.T. QFF males seek out the attractive lures and die from contacting the insecticide.

It should be noted that the QFF population does not need many males in the area to still be capable of breeding large numbers of QFF, so M.A.T. should be used in combination with other QFF controls. It’s most effective if deployed early over a wide area, and coupled with area wide protein baiting over a whole season.

M.A.T. products can be used at varying rates according to QFF pressure. Rates per hectare are recommended on the product label, along with other safety and management directions. Check product labels and plan with your agronomist for the best outcomes. For product efficacy and safety these instructions should be understood and followed at all times. It is important to change M.A.T. devices over (remove old and replace with new) at the required intervals to prevent the expired lures interfering with the chemical actions in the fresh lures.

QFF in biotrap sticky card

COVER SPRAYS – a control tool

Cover sprays are used to kill the QFF present in an area or a crop. Sprays only kill insects that come into contact with the active ingredient at the time of application or for a short time after. Some commercial fruit producers rely on covers prays to manage QFF. Home gardeners can use QFF cover sprays, however it is difficult to source the toxicant (insecticide) in some areas, mainly in areas where QFF is not a common pest.

Cover sprays are an effective tool if the efficacy of other techniques is reduced or limited. Cover sprays can be toxic to other pest insects and they can be harmful to beneficial pollinators and predators. They should be used with caution by educated and experienced operators only, as part of an integrated pest management approach. Cover sprays can also fail in poor weather or if QFF aren’t being managed in neighbouring areas.

With all chemicals, read, understand and respect the instructions and directions provided on the label. Be careful with withholding periods before re-entering the crop, and ensure Maximum Residue Limits (MRL’s) are not breached.

Commercial producers (main stream and organic) should also investigate the target market the crop is anticipated to go to as each have different market requirements and expectations around insecticide use.

**All chemical use needs to be in accordance with the label and APVMA permits and registrations

DISCLAIMER: This information is correct at the time of publication (DEC 2023). Please always check with an agronomist, industry representative, crop or market protocol requirements, and any more current labels on products with active ingredients. This document does not mention Sterile Insect Technique (SIT), as it is not yet a widely used or viable option for QFF management in the Yarra Valley. It may be a tool used in later years, and the application of SIT in the Yarra Valley will have an impact on the information tips in this document when using the QFF control tools.

This document has been put together by Bronwyn Koll, Regional Co-ordinator for the Prevention and Awareness of QFF in the Yarra Valley –funded by Agriculture Victoria’s Strategy Project “Managing Fruit Fly in Victoria 2021-2025”