General strategies for ant control include applying horticultural glue around the base of trees followed by spraying the tops of trees with an oil spray to control aphids, scale, mealy bugs. Borax is a stomach poison traditionally used as ant bait. Mix equal parts borax with icing sugar, jam or honey for ants attracted to sweetness and with pet food for ants attracted to meat. These baits are also used to kill cockroaches. Keep out of reach of children and pets. Organic products include products based on diatomaceous earth. Commercial ant powders are often based on permethrin.

Control is difficult because of the extensive network of tunnels and numerous chambers. Apply permethrin during the evening when ants are active. Leave undisturbed for at least a week. Retreat as necessary. Neem oil combined with a wetting agent applied as a thorough soaking drench can reduce funnel ant numbers. Reapply every four-six weeks. Licensed pest control operators use persistent termite control chemicals on funnel ants.

Aphids
These sucking insects attack soft new growth. Aphids are almost exclusively female, do not require males for breeding and give birth to prodigious numbers of live young. They appear in plague proportions when conditions are mild, but disappear just as quickly in extremes of temperature. Spring sees an explosion in aphid populations, but hot weather and windy conditions are enough to dispatch them. Plants with increased uptake of nitrogen (due to fertilizer application or increased rainfall) are more susceptible to attack.
(Pictured left: black chive aphids, right: aphids on roses)

Reduce plant susceptibility by changing the nutritional balance of the soil – increase levels of calcium, magnesium, silica and potash. Soap or oil sprays see [homemade remedies-Oil Spray], dusting with wood ash or a strong jet of water can help to reduce numbers. Retreatment may be necessary. Beneficial ladybeetles and their larvae prey on aphid colonies.

Once you have had this pest it is likely that it will attack future crops. Do not plant successive crops of beans next to one another or next to other legumes. Clean any local pea/bean weeds as they support fly populations. Plant beans during late autumn and winter in the tropics and subtopics. Hill compost and soil up around bean seedlings to protect stems or use paper cylinders or small pots or recycled containers with the bottoms cut out as a protective sleeve around each seed/seedling. Mulch plants. Use exclusion netting over beans. Snake beans are somewhat less susceptible to bean fly and can be planted in spring and summer.

Borer
Borer is a term that describes the damage done to plants by various insects including beetle and moth larvae. A wide range of trees and shrubs are susceptible, particularly those stressed by drought and lack of nutrients. Entire limbs can appear to die overnight. Look for evidence of sawdust-like frass or oozing sap as indications of active larvae.

Where limbs remain green it may be possible to skewer grubs with thin wire or to syringe oil-based compounds into borer holes. Seal these wounds with biodynamic tree paste (link), clay or wood putty. In most instances, you will need to prune the affected limb back below the point of borer activity. The diatomaceous earth in biodynamic tree paste is effective at preventing borer attack. Assist plants to recover by alleviating stressful conditions.

Bronze Orange Bugs
Bronze orange bugs (also known as stink bugs) The tiny green eggs of these sucking insects lay dormant in cold weather, emerging as green nymphs when temperatures rise. They change colour to yellow, then to orange and have a distinctive black spot on their backs. Mature insects are dark brown to black. They cluster in groups on new growth and flower and fruit stems, feeding through a sucking proboscis. This causes new growth to die back and flowers and developing fruit to drop. You can often detect the presence of bronze orange bugs by their smell.

If picking them off by hand, wear gloves and eye protection. These bugs secrete a caustic, acrid substance. Use a leaf blower or an old vacuum cleaner to suck them off. Oil sprays are effective at egg and nymph stages, but must applied so as to come in direct contact with the insects. Sprays based on teatree oil and/or eucalyptus including Eco-Grub control help control heavy infestations.

Cabbage White Butterfly
Cabbage white butterflies (Pieris rapae) are day-flying insects that their eggs on members of the cabbage family (broccoli, kale, cabbage, cauliflower, rocket, Asian greens etc). Crops planted outside in all but the coldest months are susceptible. Caterpillars of the cabbage white butterfly recognizable by their distinctive bright green colour, but on vegetables, this camouflaged makes them hard to spot. Install fake female cabbage white butterflies (DIY or store bought) used as fluttering, decoy butterflies discourage real butterflies from laying eggs. For more control options General control options for caterpillars. Cabbage white butterfly is often confused with the cabbage moth (Plutella xylostella). Damage and controls are similar. Image of multiple caterpillars on a kale leaf plus one of butterfly.

Case Moth
Case moth Case or bag moth is the name given to a number of different related moths that build elaborate bag-like structures to hide in during their caterpillar stage. The case is typically leathery with small sticks and leaves cleverly woven together. The head emerges from one end of the nest to feed on plant foliage, but retreats into its protective cover whenever threatened. It pupates in the nest and ultimately turns into an adult moth. The image here shows the size of the caterpillar when the bag has been carefully cut open with scissors. These insects are a great curiosity, but rarely do enough damage to warrant action. Various species of Ichneumon wasps prey on case moth larvae.

Caterpillars
Caterpillars are the larval stage of moths and butterflies. Few gardeners worry about a couple of chewed leaves if it means they can enjoy butterflies. However, there are around 20 times more moth species in Australia than butterflies and many moths are imported pests responsible for significant damage to ornamental and edible plants.

General control options for caterpillars:
Inspect and hand pick off egg clusters and young caterpillars regularly; encourage beneficial insects including predatory wasps; use exclusion netting to keep moths and butterflies from landing and laying eggs; apply molasses or chilli sprays; [refer to 'homemade remedies']. Use a recycled hose end connected applicator containing molasses spray for shrubs and large trees. Use insect zapping lights during the evening when night-flying moths are active. Apply commercial Bacillus thuringiensis sprays (BT/Dipel). Pheromone lures for monitoring some moth species are available from Bugs for Bugs. See specific caterpillar types for further control options.

Cluster Caterpillar
These caterpillars are the larvae of nocturnal, beige/brown-coloured moths (Spodoptera species). They are major pests of a wide range of crops. Other common names including oriental leafworm moth, cotton leafworm/cutworm, rice cutworm, tobacco budworm/cutworm, tropical armyworm and taro caterpillar. Larvae colours and patterns vary with age, but all stages are voracious feeders that cluster in gregarious groups. Eggs and larvae can lay dormant and appear rapidly after rain. Multiple generations of moth eggs are laid in one season. For control options see [General control options for caterpillars].

Codling Moth
Codling moth (Cydia pomenella) is associated with pome fruit like apples, pears and quinces. The moth lays its eggs prior to flowering. They hatch into larvae that tunnel into young fruit. They eat out the fruit, emerging when they are ready to pupate. The lifecycle continues beneath the tree in leaf litter or in cracks and crevices in the bark.

Control eggs and young larvae prior to flowering with oil sprays, BT, pyrethrum sprays; physically protect fruit with bags (ensure larvae are not already inside); collect and catch pupating larvae via trunk collars that act as pupa collecting places or with sticky barriers; install pheromone traps. Collect any infected fruit and feed it to livestock or put in buckets then fill with boiling water. Leave overnight before hot composting. Trigogramma wasps and pathogenic nematodes are used for commercial control. Image Apple with codling moth damage and tree of bagged fruit

Curl grubs are eaten by bandicoots. Small conical holes in lawns or larger excavations within gardens are signs of bandicoot activity. Wasps also parasitise curl grubs by piercing the skin and laying their eggs inside. The young wasps hatch and live inside the body, eating the non-essential tissues of the curl grub before finally emerging through the body wall of the larvae and ultimately causing its death. Larvae of the African black beetle and scarab cockchafer that attack lawns may warrant control. Drench or spray affected plants with molasses spray, [refer to 'homemade remedies']; use tea tree based products like Eco-Grub; apply spinosad sprays. Repeat applications may be required during spring, summer and autumn. See also [Lawn grubs]

Cycad Blue Butterfly
This small, native butterfly lays eggs in the centre of cycad plants prior to the new fronds emerging. Fronds either fail to appear or are permanently ruined by the chewing of the slug-like larvae. Ants on cycads are often an indication of the presence of larvae on the undersides of the fronds. Consider Zamia furfuracea as an alternative. It is immune to attack from the cycad blue butterfly.

Tuck exclusion netting loosely over the centre of the plant prior to new growth emerging. Leave room for the new fronds to gradually push it off as they mature. Mature fronds are resistant to attack. Household surface spray applied misted in the heart of the plant at a 1m distance (to avoid burning by propellant) helps protect plants. Apply this during the cool of the evening. For more control options see General control options for caterpillars.

Dendrobium Beetle
This is a common pest of potted and shade house orchids, but also attacks orchids grown in tree forks or other natural settings. Beetles and their larvae destroy new leaves and stems of orchids. Clean up any old pots and any other waste materials near the orchids or in your orchid house as this may harbour beetles. Squash them by hand. Apply chewing insect controls such as diatomaceous earth sprays.

Dodder
The appearance of yellow, orange or green cotton or string-like threads covering plants indicates infestation by a parasitic plant known as dodder. Seeds are distributed by birds. Dodder is difficult to get rid of. Germinating seeds attach themselves to living plants, drawing on their host for nutrients. They can also carry out their own photosynthesis. This dual nutrient source explains why dodder is able to grow so quickly. The only option for control is complete removal. Dodder invades the tissue of the host plant in order to feed from it. If plants in your garden become unwitting hosts, severe pruning or complete removal of the plant is the only option for eradicating this parasitic pest. These are more than 90 different species of dodder that are native to Australia.

Erinose Mite
Erinose mite is most common on hibiscus, lychee, melicope and Eumundi quandong. On hibiscus they create distorted new growth. On other species the leaves take on a brown, felt-like appearance. Control can be achieved by pruning off the worst affected areas (note this disrupts lychee fruiting). Spray with wettable sulphur or apply an oil spray to both sides of the leaves [see Do It Yourself Pest Control]. Timing is all important. Check plants regularly and spray new growth. Pale mottling is often the first indication of infestation. Damaged new growth and foliage does not retain its former appearance after spraying controls the mites.

Fruit Fly
Understanding the lifecycle and passions of Queensland fruit fly can help you achieve a ‘wriggle-free’ harvest. Virtually all fruit are potentially susceptible including tomatoes, capsicum, chillies, eggplants, citrus, grapes, feijoa and tropical apples and stone fruit. A fruit fly lifecycle includes an egg, larvae (maggot), pupae and adult stage. Eggs are laid in fruit by female flies after they have mated. This fruit is described as being stung. The eggs develop into the familiar white maggots (fruit fly larvae). Feeding maggots cause fruit to rot. Maggots emerge from the fruit and drop to the ground. Fruit attacked early in the season will partially ripen and drop prematurely. Fruit flies pupate in the ground, emerging weeks or months later to mate and sting fruit.

Spraying is not a control option. In some cases it is possible to pick fruit before it is fully ripe, thereby beating the moths to the harvest. For crops that require a greater degree of ripening, cover fruit with paper bags or exclusion fabric. Outdoor light designed to zap night flying insects attract these moths. A standard moth trap baited with over-ripe bananas will attract fruit piercing moths. [video link of fruit piercing moth]

Gall Wasp
Swollen lumps on the young stems of citrus trees signal egg-laying activity by the gall wasp (Bruchophagus fellis). This stout, black wasp is native to NSW and Queensland. The lumps enlarge as the wasp larvae grow. Eggs are laid in summer and early autumn when new growth peaks. Wasps emerge from the galls from mid winter in the tropics and subtropics and in spring in cooler climates. Small, native orange wasps parasitize the larvae of citrus gall wasps. Remove the affected stems at a leaf joint below the lump. Cut the swollen section of stem open, if mulching or composting the waste to expose eggs and larvae inside to dehydration. Alternatively, dispose of affect stems offsite or by burning. It is not essential to remove old galls from attacks except for cosmetic reasons, as the larvae will have already departed.

Harlequin Bugs
Cotton harlequin bugs can be found on members of the cotton or Malvaceae family. This includes hibiscus, malvaviscus, abutilon and mallow.  The metallic blue sheen of these bugs makes them easy to spot, particularly as they congregate in large numbers. The large, comparatively dull coloured, orange females tend to be solitary. Female bugs lay groups of pale pink eggs in neat clusters that encircle the stem. You will often find her standing guard over newly laid egg clusters. Like all bugs, cotton harlequins are equipped with a long, sucking proboscis. They use this tube to pierce the leaf surface and draw out the liquid contents of the stem and leaf cells. Cotton harlequin bugs rarely warrant control. Occasionally, the ends of heavily infested stems droop under the weight of the insects and appear wilted as a result of their feeding activity. Prune off affected stems after the insects have had their fill.

Hibiscus Beetle
Hibiscus beetles have always been notoriously difficult to control because of their hard outer shell and tendency to shelter out of reach within flower petals.  The beetles cause flowers to fall from plants prematurely. Cultivars with white or pale coloured flowers tend to be more attractive to hibiscus beetles. Gardeners have several strategies to reduce beetle populations. Picking up fallen blooms each day reduces beetle numbers significantly. Placing white or yellow icecream containers filled with water and a liquid liquid soap beneath plants can trap a significant number of adults. Traps should be emptied every few days and refilled with fresh water and soap.  

Lacebug
These sucking insects feed on the undersides of new growth during late spring, summer and early autumn. The foliage becomes mottled and pale. The rust-like lacebug droppings on the underside of the leaves remain well after the insects have departed. Azaleas and olives are particularly affected. Olive lacebug causes significant leaf drop on olive trees. Soap or oil sprays, and even liquid fish fertiliser (it contains some fish oil) are effective at controlling these pests, but you may need to repeat spray at fortnightly intervals. Make sure you apply sprays to the undersides of the leaves. Use a recycled hose end connected applicator to apply oil spray to shrubs and large trees.

Ladybeetle (Twenty-eight Spotted)
Most lady beetles are beneficial; however the 28 spotted lady beetle feeds on the leaves of plants. Lady beetles with a few spots are likely to be beneficial as both adults and their larvae feed voraciously on pests such as aphids, scale and mites. Lady beetles with lots of black spots (24-28) on a yellow/brown body (pictured) are leaf eaters that commonly attack potatoes and eggplants, but also feed on pumpkins, rockmelons and other vegetable crops. They often migrate from weeds to vegetables or ornamental plants. Remove any weeds that might harbour them. Squash them by hand.

Leaf Miner
Leaf miners are larvae of night-flying moths whose larvae tunnel between the upper and lower leaf surfaces of plants. Ornamental plants including cineraria and nasturtiums are often attacked, but also native plants like banksia. Citrus leaf miner causes most concern among gardeners. Leaf miners are naturally controlled by a number of beneficial wasps. Remove affected leaves on ornamental plants if they look unsightly (see Citrus leaf miner below).

Lerp
This insect is a psyllid, but commonly called a lerp. This is really the name of their lacy, sugary coating that the insect hides beneath. Rather than produce honey dew like many other sucking pests, psyllids produce highly decorative (and edible) lerp coverings. They come in all shapes and sizes with some appearing remarkably like tiny seashells. These insects tend to occur on eucalyptus trees grown outside the limits of their climatic tolerance. Rather than try to control these insects, you should look at the overall health of the tree and try to provide the type of conditions that the tree would experience in its natural environment.

Longicorn Beetles
Native longicorm beetles are easily distinguished by their rectangular body shape and enormous recurved antennae. The female beetle removes the outermost section of tissue, ringbarking pencil-thick sections of stem with remarkable precision. She lays eggs just beneath the bark in the area immediately beyond the ring. The tree continues to transport water and dissolved minerals from the root system to the foliage via undamaged water conducting tissue located on the inside of the stem.

Sugars produced by the foliage are sent down to the roots, but are interrupted by the tissue damage at the point where the eggs are laid. This provides an abundant food supply for the developing longicorn larvae. Affected trees attempt to repair the damage by producing callous tissue to close the ring-barked gap, but the affected stem section usually dies. To control infestations, prune dead stem sections back to a growing point. This will reduce beetles numbers. Alternatively, think of it as natural pruning.

Mealy Bugs
These sucking insects hide on the undersides of leaves, in leaf axils or on plant roots. They suck sap and weaken plants and are often associated sooty mould and ants. They are very difficult to control. Soil dryness can predispose plants to infestations. If you find the new leaves of bulb plants (agapanthus, clivia, eucharis lilies etc) emerging with distorted foliage – it is likely mealy bugs have infested the roots. Hibiscus, palms, roses, African violets and indoor plants are commonly attacked, but mealy bugs have a very wide host range.

Dispose of badly infested indoor plants off-site to stop pests spreading to other pots. Where mealy bugs on roots are suspected, drop the entire plant into a bucket of a strong molasses solution (2 tablespoons per litre water) or a combination of neem and a soil wetting agent. Leave to soak overnight. Dip a cotton wool bud in methylated spirits and apply directly on the pest. Botanical oil sprays can also be used, but are not suitable for palms, very soft foliage plants like ferns or those with hairy leaves like African violets. Use neem sprays combined with a wetting agent to drench the soil around garden plants where root systems are infested. Where infestations are serious or continue to occur, consider buying in predatory mealy bug eating lady beetles.

Mites
Mites are not insects, but closely related to spiders and ticks. They are largely impossible to see with the naked eye, but symptoms of attack are easy to spot. There are many different species including Broad mite; Brown rust mites; Bud mite; Erinose mite; Tea mite; Red spider mite or two spotted mite and russet mite. Dry conditions often increase the incidence and severity of mite infestations. If sowing seed, freeze it 48 hours prior to sowing to kill mites carried on seed. Dispose of small annual plants off-site if they are infested. Dusting sulphur, wettable sulphur, diatomaceous earth or wood ash pressed on to affected foliage and stems helps to control mites.

Pimple Psyllids on Lillypilly
Pimple psyllids are sucking insects that cause puckering and distortion on the new grow of lillypilly plants. The insect creates a pimple-like bump on the leaf to hide under. If you look closely you can often see this scale-like insect, however even when the insect departs, the lump remains. Very few lillypilly trees are immune to this pest, but Syzygium 'Pink Cascade' is one of them. Select lillypilly varieties carefully. Prune foliage from affected plants, then spray the new growth with oil [refer to 'homemade remedies] or neem and repeat spray whenever plants make significant new growth.

Possums
To protect fruit and selected plants from being eaten by possums, provide an alternative food source like carrots. Accept that these native animals need to eat some plants and most of the plants they feed on recover quite quickly. To create a repellent barrier around selected fruit trees or vegetable gardens, spray oil of cloves at the rate of 6 drops per litre of water each week. On citrus and other plants with hard leaves the spray can be applied directly to the plant.

Rat Damage
No-one likes to admit that they have rats or other rodents in the garden and poor possums often get the blame for damage like this. Rat damage is easy to spot as you can clearly see the gnaw marks from a rodent's front teeth. Rats are typically also to blame if you see passionfruit with a neat circular hole in the shell and an empty fruit. Rats and mice feed on sweet potatoes, fallen fruit, macadamia nuts, pellets of fertiliser applied to gardens and controlled release fertilizer found in potted plants. Rat controlled can be achieved through humane traps.

Sawfly Larvae (also spitfires)
Sawflies or spitfires feed on eucalyptus foliage. They are not flies, but wasp larvae. Adult wasps pupate in the soil (often for years). They emerge in spring and summer. Females use a modified egg laying structure to ‘saw’ into the leaf to lay eggs (often parthenogenetically – without the need to mate). The eggs develop into gregarious, hideous-looking spitfire larvae - a name that describes their habit of writhing up and regurgitating an acrid liquid to repel predators. The native plant species they attack cope with the defoliation that accompanies an infestation of sawfly larvae, so control is not usually necessary. You can prune off large numbers of these simply by cutting off the leaves that they cluster on. Molasses or chilli sprays [see Do It Yourself Pest Control] will also cause them to drop off. Birds and poultry do not eat them.

Scale
There are many different species of sucking scale pests including hard wax scale (Ceroplastes sinensis), white wax scale (Ceroplastes destructor) and pink wax scale (Ceroplastes rubens), black scale (Saisettia oleae) and soft brown scale (Coccus hesperidum). Almost all plants are potentially affected. Scale insects are commonly associated with ants who harvest honey dew exudate produced by the scale. Black sooty mould fungus grows on the honey dew. Oil sprays [see Do It Yourself Pest Control] will control scale and eventually the sooty mould will also disappear. Apply fortnightly for six weeks (3 times) to control new generations of scale that emerge from beneath the body of mature scale killed by initial applications. Lady beetles and beneficial wasps prey on scale pests. See also Seychelles soft scale

Scale on Grass Trees
Scales pests often hide deep within the foliage head of native grass trees. Standard treatments are rarely completely effective. The natural solution is fire. Use a small gas blow torch or the type you use in the kitchen to caramelise sugar to simulate a bush fire. Burn the head of the plant you will toast the scale! Take the necessary precautions to prevent the fire spreading. Treated plants develop a fresh green head of foliage.

Snails and Slugs
Slugs and snails are molluscs. Some eat plants; some eat moss and fungi; some prey on other snails and slugs. Saucers of homemade bee attract snails and slugs. Non-toxic iron-based baits are the safest of the snail and slug pellets commercially available. Thin copper bands sold through some nursery outlets and mail order companies make effective barriers. Simply place the copper around the edge of the garden bed, fixing it to timber edging or brickwork. As snails and slugs attempt to pass over the copper barrier they receive an electrical shock that repels them. Clear dead leaves from the base of plants with strappy foliage. Clean up pots and other materials where slugs and snails hide. Poor the waste from your coffee plunger or spread coffee grounds over areas where snails and slugs congregate. They hate caffeine! The large native red triangle slug (pictured above left) eats mould and algae and does not damage plants.

Spined Citrus Bug
These sucking insects vary in colour when young. Adults are leaf green with the appearance of pointed shoulders and are well camouflaged. They feed by piecing the fruit of a variety of citrus and sucking up the liquid contents. Fruit develops dry patches and premature fruit fall is common. Lemons and mandarins are particularly susceptible. Even a small infestation can do considerable damage to your harvest.

Wear gloves and pick them off by hand or use a leaf blower or vacuum cleaner to suck them up. Oil sprays [see Do It Yourself Pest Control] or neem (on non-fruiting trees only) can be effective, but needs to be applied directly to the insect.

Thrips
Thrips are slender black or grey sucking insects that commonly attack flowers and developing fruit. Their feeding activity can cause premature flower drop; failure of flowers to set fruit; flower deformities and twisted, puckered or malformed fruit. Plants commonly affected include beans, tomatoes, onions, gardenias, azaleas, roses, bulbs and native plants. Thrips are very hard to spot. To check for thrips, cut a few blooms and place them in a clear plastic bag or a glass jar. Leave overnight and by the morning you should be able to spot the insects that have emerged from the blooms.

Weevils
Weevils are a type of beetle and are easy to recognise because they have a large snout. Some weevils are incredibly colourful, while others are plain black or brown. Some chew leaves and stems; others feed on roots or fruit. In most cases control is not warranted. Please note: These are not the weevils that you find in flour or grains which are typically the larvae of moths (Plodia interpunctella or Kuehniella species), Pantry moths are typically in products when you buy them and emerge during storage. To kill pantry moths place flour and grains in the freezer for 48 hours, then store in sealed containers in the pantry or in the refrigerator.

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