Current Page -  Identify the pest     

Picture The Pest
Azalea Lacebug
Broad Mites on tomatoes
Bronze Orange Bugs
Camellia Tea Mite
Case Moth
Camellia Tea Mite
Case Moth
Caterpillar in Tomatoes
Citrus Gall Wasp
Codling Moth
Crinum Grubs
Curl Grubs
Cycad Blue Butterfly
Dendrobium beetle

Fruit Fly
Fruit Spotting Bug Damage
Fruit Sucking Moth
Harlequin Bugs
Hibiscus Beetle
Leaf Miner
Lily Caterpillar
Longicorn Beetles
Mealy Bugs

Mite Damage on Citrus
Nematodes (see Diseases)
Rat Damage
Red spider Mite
Sawfly Larvae
Scale on Grass trees
Scale & Ants
Snails & Slugs
Sod web worm moth
Spined Citrus Bug

Tomato Russet Mite

Webbing Caterpillar
White Butterfly

White Rose Scale

These tiny sucking insects attack the soft new growth of anything from lettuce to roses and eucalypts. Aphids are quite remarkable insects. They 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. Soap sprays, oil sprays see [homemade remedies-Oil Spray] or a strong jet of water can help to reduce numbers until voracious, beneficial ladybirds and their larvae discover and eat their way through entire colonies.

Ants-Mini Movers
Have you noticed little mounds of soil appearing overnight in lawns around your suburb? These mini volcanos are created by industrious creatures called funnel ants (Aphaenogaster pythia). The exact number of ant species in Australia is unknown, but experts estimate there could be as many as 5,000. There are several species of funnel ants including the pasture funnel ant (most common in Brisbane) and forest funnel ants. Funnel ants tend to appear after rainfall when the soil is moist. The mounds are formed from soil excavated from underground tunnels. If you want to see the ants in action you must be prepared to venture out after dark. Shine a torch into the top of the mound and you will see small worker ants methodically carrying grains of soil to the surface, often guarded by larger protective soldiers. Pasture funnel ants prefer lawns rather than garden beds covered in leaf litter or mulch. They also avoid lawn areas where the soil is compacted or heavy clay. What they love are gardens where imported turf has been laid. It is not the type of grass, but the fine, light sandy soil that comes with the turf that they seem to prefer. Funnel ants are amazing earth movers, building mounds you can easily trip over. The aeration they achieve below ground is significant. The depth of the nest varies depending on your soil type. The subsoil beneath my lawn is hard and compacted, so the nests do not appear to be very deep (20-30cm), but in lighter soil it is possible for them to tunnel to a depth of a metre or more. Mysteriously, they spend much of their lifecycle completely below ground, feeding on sugary secretions of soil mealy bugs, scale and plant root exudates. In most cases, commercial pest control operators are employed to control of funnel ants, but I have been keen to try a few other options. Standard ant powders based on permethrin are quite effective when sprinkled into the top of each funnel. Do this in the evening when the ants are active, guided by a torch or outdoor lighting. Leave the dust undisturbed for at least a week before attempting to level the mounds. It is likely that you will miss a few smaller mounds and not all ants will be killed where nests are deep, so be prepared to retreat as necessary. Treatments for lawn grubs (African black beetle and armyworm) based on eucalyptus and tea tree oil (EcoGrub), coincidentally also appear to reduce funnel ant numbers. Products need to be thoroughly drenched through the soil, so you may find it more effective to apply with a watering can rather than a hose connector. Once again it is best to apply late during the day when the ants are more likely to be closer to the surface. Some gardeners simply head outdoors with a kettle of boiling water each evening, treating a dozen mounds at a time as a means of managing small infestations.
Article by Annette McFarlane SundayMail 31/07/2016

Azalea LacebugAzalea Lacebug
These sucking insects feed on the new growth of azaleas during spring and summer. If you look closely at the undersides of the leaves you will be able to see the insects if they are still active. The foliage of affected plants becomes mottled and pale, and the rust-like lacebug droppings on the underside of the leaves remain well after the insects have departed. In fact, most gardeners only notice this problem in autumn after the insects are long gone. Minimise the damage by using a sharp jet of water under the leaves every time you hose. Soap sprays and liquid fish fertiliser (it contains some fish oil) are also effective, but make sure you apply these to the undersides of the new growth.

Citrus BorerBorer
There are several different species of insects especially beetles and moths whose larvae attack a wide range of trees and shrubs. Plants stressed by drought and lack of nutrients are most likely to fall victim. Entire limbs can appear to die overnight. Look for evidence of sawdust-like frass that indicate active larvae. Where limbs remain green it may be possible to skewer grubs with thin wire or syringe oil-based compounds into borer holes, then seal the tree wounds with clay or wood putty. In most instances, you will need to prune the affected limb back below the point of borer activity. Assist plants to recover by alleviating stressful conditions.
More Pictures of Borer [Citrus Borer] [Borer in Murraya]

Broad Mite on Tomatoes
Broad mite (Polyphagotarsonemus latus) is a major pest of tomatoes, capsicum, chilli and eggplant and many other plants. New foliage and young fruit display distorted, stunted and often thicken foliage. Developing fruit may be completely bronzed - almost looking as if the fruit have a thick coating over the fruit. A simple soap spray or wettable sulphur will control outbreaks, but damage foliage and fruit does not repair. If you have had issues with broad mite in the past, apply repeat preventative sprays when plants are young and at early fruit formation.

Bronze Orange BugsBronze Orange Bugs
The eggs of these sucking insects lay dormant over winter, emerging as tiny, green nymphs when it warms up. Bronze orange bugs or stink bugs, change colour from yellow to orange as they grow 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.

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. Pyrethrum and botanical oil sprays are also effective, especially at nymph stages.

Cabbage White ButterflyCabbage White Butterfly
Cabbage white butterflies love to lay their eggs on members of the cabbage family like broccoli, kale, cabbage, cauliflower and Asian cabbage greens. Crops planted outside the ideal growing months of April through until August are more susceptible. Netting crops will keep butterflies from landing and laying eggs. Molasses sprays (1 tablespoon molasses per litre water with a few drops of soft soap) are very effective and have both a repellent and protective effect, but need to be applied regularly. Other organic options include sprays such as Success and Dipel, but again repeat applications may be required during the growing season.

Camellia Tea MiteCamellia Tea MiteCamellia Tea Mite
Camellias provide great flower colour during the cooler months in many parts of Queensland and Northern New South Wales. But just when you expect them to look their best, the foliage can develop a bronze discolouration down the central midrib of the leaf, signalling attack by camellia tea mite. Left unchecked, bronzing envelops the entire leaf and poor growth and reduced flowering result.

A simple oil spray applied to both sides of the leaves will bring the problem under control, but do not expect affected leaves to regain their former appearance. Regular use of fish based fertiliser can also help prevent the problem. The fish oil contained in the fertiliser often leaves sufficient oil residue on the foliage to control mite outbreaks. You can also make your own oil spray [refer to 'homemade remedies'].

Case MothCase Moth
The case or bag moth builds itself an elaborate protective nest or bag in which to hide while it is in its larva or caterpillar stage. The case is leathery with small sticks cleverly woven into the surface to provide strength and camouflage. It's head emerges from one end of the nest while it feeds on plant foliage, but it retreats completely back into its protective cover whenever it feels threatened. It pupates in the nest to go through metamorphosis 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 much damage to plants. They are easy clipped from plants if you feel this is necessary.

Caterpillar in Tomatoes
The helicoverpa caterpillar attacks a wide range of vegetables. The key thing to understand in terms of tomatoes is that this pest attacks plants at flower stage. The adult moth lays its eggs on the leaves or flowers and the tiny caterpillar quickly burrows its way into the pinhead sized fruit. The fruit look perfect and continue to develop. Just when you think you are getting close to harvesting you may discover some holes where the fully gorged larvae has emerged to pupate in the soil below. Alternatively, you may not discover the grub until you cut into a ripe fruit. Control is relatively simple (BT/molasses/chilli sprays), but timing is everything. Start treating tomatoes prior to flowering, which really means just a few weeks after planting.

Citrus Gall WaspCitrus Gall Wasp
Swollen lumps on the young stems of citrus trees signal egg-laying activity of the citrus gall wasp. The lumps on the stem enlarge as the wasp larvae grow. Eggs are laid in summer and early autumn, but young wasps will not emerge from the galls until winter. Use sharp secateurs to remove the affected stems at a leaf joint below the lump. Curious gardeners may like to cut the swollen section of stem open to view the tiny, maggot-like larvae, if only to be convinced they are the cause of the problem. Dispose of the affected stems and you will have significantly reduced next year’s population of adult wasps. It is not essential to remove old galls from attacks that have taken place in previous seasons, as the larvae will have already departed. You may however remove old galls for purely cosmetic reasons.

Codling Moth
Codling moth (Cydia pomenella) is a problem commonly associated with pome fruit like apples, pears and quinces. The moth lays its eggs prior to flowering and these quickly hatch into larvae that will ultimately tunnel their way into the young fruit as they develop.They eat out the apples as it develops, emerging when they are ready to pupate. They then continue their lifecycle beneath the tree in leaf little or in the cracks and crevices of bark. Control strategies are targeted at pre flowering control of eggs and young larvae (BT, botanical oil, pyrethrum sprays); physically protecting fruit with bags (make sure larvae are not already inside); collecting and catching pupating larvae (via trunk collars that act as pupa collecting places or sticky barriers); pheromone traps. Hygiene is also important, so always collect infected fruit and feed it to your chooks/ducks/horses/cows or other animals.

Cycad Blue ButterflyCycad Blue Butterfly LarvaeCycad Blue Butterfly
The cycad blue butterfly has become an increasing problem for gardeners over the past decade. This small butterfly lays eggs in the centre of the plant, often prior to the emergence of the new fronds. The new fronds either fail to emerge or are permanently ruined by the chewing of the slug-like larvae. The presence of ants on cycads is often an indication of the presence of larvae on the undersides of the fronds. Any organic products that control caterpillars (including molasses and spinosad sprays) will control this pest, but must be applied before the larvae being to chew the new foliage. Correct timing is essential. I prefer to cover the centre of each plant with a small section of soft, green, mosquito netting, prior to frond emergence. Tuck it loosely over the centre of the plant leaving room for the new fronds to gradually push it off as they mature. Covering with ting keeps plants free of larvae and once the fronds become hard they are immune to attack. If you are not prepared to go to this effort consider an alternative plant. Zamia furfuracea (a close relative of the cycad commonly known as the cardboard palm) is immune to attack from the cycad blue butterfly.

Caterpillar DamageLily CaterpillarCrinum or Lily Grubs
These tiny caterpillars (Spodoptera picta) burrow into the centre of crinum lilies, eating out the succulent heart of the plant. But don’t make the mistake of thinking their diet is limited to crinum species. They find hippeastrum, clivea and agapanthus equally appealing. Young caterpillars have black and white stripes, but mature caterpillars develop yellow stripes. The adult is a medium-sized brown and cream moth. Over the autumn and winter period, crinum grubs can eat out the heart of plants. What remains simply rots away. Clear away any old foliage and drench the centre of plants with molasses and water (1 tblspn per litre water). The drench should come in contact with the grub. Retreat regularly as moths revisit plants to lay new infestations.

Curl Grub Larvae

Curl Grubs
When digging the garden or making compost you may come across larvae that are white in colour, have a characteristic ‘C’ shape, three pairs of legs and a distinctive head and abdomen. Commonly known as curl grubs, they are beetle larvae (including Christmas beetles, cane beetles, dung beetles, flower scarabs and rhinoceros beetles). The larvae vary in size with the large rhinoceros beetle larvae (pictured) growing up to 70mm long. 

The beetles lay their eggs in the soil during late spring, summer and early autumn. The eggs hatch into larvae that feed on plant roots or decaying organic matter. The larvae grow and pupate during late autumn, winter and early spring. Curl grubs are favourite bandicoot fare and small conical holes in lawns or larger excavations within gardens are the telltale 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 or spinosad sprays like Success . Repeat applications may be required during spring, summer and autumn.

Dendrobium beetle!
This is a common pest of potted and shade house orchids, but as you can see, will also attack orchids grown in tree forks or other naturalistic settings. Beetles and their larvae destroy new leaves and stems of orchids, so control them if you can. Squash them by hand (like I did this one) or try using any organic chewing insect control (Spinosad, diatomaceous earth, molasses drenches etc).

The appearance of yellow or orange cotton-like threads covering roadside grasses, signals the seasonal return of the parasitic plant known as dodder. Seeds are distributed by birds and the plant is frustratingly 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 of dodder 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 to an infestation of dodder, severe pruning or complete removal of your treasured garden plant is the only option for eradicating this parasitic pest. These are several different species of dodder, several of which are native to Australia.

Erinose MiteErinose Mite
Mites are invisible to the naked eye, but in the case of erinose mites it is easy to spot the damage they cause. On plants like lychee, melicope and Eumundi quandong, the leaves take on a brown, felt-like appearance. On hibiscus you will notice distorted, knobbly new growth. Control can be achieved by pruning off the worst affected areas and spraying with wettable sulphur or a botanical oil spray (home make oil spray or Eco-Oil). Timing is all important. Check plants regularly and spray new growth when you see any pale mottling as this is the first indication of mite infestation.

Fruit Fly
Understanding the lifecycle and passions of Queensland fruit fly can help your achieve a ‘wriggle-free’ harvest Remember that virtually all fruit are susceptible especially tomatoes, capsicum, eggplant, Meyer and Lots A Lemons, thin-skinned grapefruit and grapes. Fruit fly have an egg, maggot, pupae and adult stage in their lifecycle. Use baits all year round to monitor populations and act as traps. Inspect, empty and refill traps regularly. Know what you are catching. Grow susceptible crops when fruit fly population is low. Place bags over individual fruit immediately after fruit set or cover entire vegetable gardens or fruit trees with exclusion fabric. For more information including examples of commercial traps, what they contain and attract, plus a bait recipe used by biodynamic gardeners click here.... (pdf)

Fruit Sucking MothFruit-Sucking Moth
When near ripe fruit develop soft spots that cause premature ripening, fruit fly is often to blame. Breaking open the fruit will reveal tell-tale larvae that help to confirm the diagnosis. When no larvae are present, suspect attack from the fruit-sucking moth. As moths are active at night, few gardeners ever encounter them.  Fruit-sucking moths are large, with a wingspan of 5-6cm. The wings are typically dark brown with distinctive orange markings. The moths pierce the skin of pawpaws, tomatoes, citrus, persimmons, bananas and other fruit, then suck out the liquid contents. A black spot remains at the point of entry, with flesh around this either becoming soft and pulpy or dry and pithy, depending on the fruit attacked.

Spraying to control moths is not an 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, try covering fruit with paper bags or cotton cloth secured with a clothes peg. If you have an outdoor light designed to zap night flying insects, leave it on overnight. Many gardeners report significant reductions in the incidence of pest problems caused by adult moths, caterpillars and beetles using this method. It is also possible to make a moth trap baited with ripe fruit.

Harliquin BugsHarlequin 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 BeetleHibiscus 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.  

Twenty Eight Spot LadybirdLadybird (Twenty-eight Spotted)
We have all grown up believing that ladybirds are beneficial insects and most of the over 300 different species of these insects are welcome in our gardens. Unfortunately, there are a few species that feed on the leaves of plants. Telling a good ladybird from a bad one is a matter of counting the spots. Ladybirds 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. Ladybirds with lots of black spots (24-28) on a yellow/brown body (pictured) are leaf eaters commonly known as twenty-eight spotted ladybirds.

These ladybirds are common pests of solanaceous plants such as potatoes and eggplants, but also attack pumpkins, rockmelons and other vegetable crops. They also feed on weeds and often migrate from weedy areas of the garden to vegetables or ornamental plants. If twenty-eight spotted ladybirds reach plague proportions, remove any weeds that might harbour them, squash them by hand or spray with pyrethrum. 

Citrus Leaf MinerLeaf Miner
Citrus leaf miner (Phyllocnistis citrella) is the larvae of an introduced moth. The female moth lays her eggs and the larvae quickly burrow between the upper and lower leaf surface of young foliage. The foliage becomes twisted and puckered as the larvae mines and eats its way through the leaf. Heavy infestations disfigure trees and can retard growth, particularly on young trees.

On small trees or those in containers, simply squeezing leaves between your thumb and forefinger can kill the larvae within the leaf. Pruning off affected leaves is another alternative. Female moths avoid leaves sprayed with plant based horticultural oil. Spraying should coincide with new growth flushes. Mandarin trees and Meyer lemons are particularly prone to citrus leaf miner. Infestations on mature trees is largely cosmetic and rarely warrants control.

You typically find these insects on gums with trees grown outside their normal climatic or geographic range being particularly susceptible. The insect is a psyllid, but they are more commonly known as lerps. The lerp is really the sweet, lacey, sugary coating that this tiny sucking insect hides beneath. Some sucking insects like aphids product sugary honeydew, whereas these psyllids produce the highly decorative (and edible) lerp coverings. They come in all shapes and sizes with some appearing remarkably like tiny seashells. 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 Beetle DamageLongicorn Beetles
These intriguing lines indicate native longicorn beetles have been hard at work. Longicorns 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 then lays her 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. The longicorn larvae have had their fill by the time this occurs. To control infestations, prune dead stem sections back to a growing point.

Mealy BugsMealy Bugs
These sucking insects hide on the undersides of leaves, in leaf axils or on plant roots. They are quite hard to control and if you find them on indoor plants like African violets it is often better to simply dispose of the plant in the garbage. You do not want these pests spreading to other plants (do not compost unless you kill the pests first).  If you find the new leaves of potted plants such as eucharis lilies emerging with distorted foliage - suspect mealy bugs within the potting mix. Dropping the entire plant into a bucket of a strong molasses solution (2 tablespoons per litre water) can control outbreaks. Leave the pot to soak for several hours. Some gardeners also use a cotton wool bud dipped in methylated spirits applied directly on the pest. Botanical oil sprays can also be used, but are not suitable for plants with very soft foliage or hairy leaves. Eco-Neem may also be used. 

You find them from time to time in the garden or in pots, but they usually do not cause much of a problem here in Qld. They do occur in plague proportions in cooler climates. You seem to have quite a few, so you might want to do something about them. They feed on damp organic matter and hide under leaf litter, in unused pots, or other things around the garden. If you have piles of damp newspapers or other things they can hide in you might want to clean this up. If they have no-where to hide, they tend to move on. Diatomaceous Earth or Boric acid available from Green Harvest can be used to control them. You just sprinkle this around where they are active.

Maori MiteCitrus Bud MiteMites
Mites are microscopic plant pests that are more closely related to spiders and ticks than insects. Symptoms of infestation are varied and include loss of leaf colour, drying and cupping of foliage, grey or rusty foliage, fruit discolouration, distorted growth and rind hardening on citrus.

There are many different species of mites. Some common types include broad mite, red spider or two spotted mite (pictured), erinose mite (attack hibiscus and lychee), camellia tea mite, citrus russett mite previously called Maori mite (pictured), bulb mite (attack a range of bulb species), citrus bud mite (pictured) and tomato russett mite.

Dry conditions often increase the incidence and severity of mite infestations, particularly red spider
Red Spider Mitemites. Fine Red Spider Mitewebbing can often be seen where plants with serious infestations.

Palms keep indoors and a range of other indoor or patio plant species are particularly subject to red spider mite infestation. Water plants outdoors each week, taking care to spray the hose up underneath the foliage as this is where mites hide and feed. This will help to dislodge them and keep plants free of serious infestation. Wiping both sides of the leaves with a soft cloth dipped in warm, soapy water can also help.

Lemons and navel oranges seem particularly prone to mites. Spraying plant based oil sprays will suffocate mites. Soap sprays or wettable sulphur kills mites through dehydration. Be alert for the symptoms of mite attack and apply sprays as soon as the condition becomes obvious.

Mite Damage on Citrus
Take a close look at your citrus blooms (these are from a Minneola tangelo) and you may observe some distorted flowers and developing fruit. These blooms have been affected by bud mites (most likely Eriophyyes sheldoni). Sulphur or oil sprays can be used as a preventative, but once flowers and young fruit have been affected the damage is already done. Pick them off if you like. Fruit typically still develops, but will be distorted.

Root Knot Nematodes (See Diseases)

Pimple Psyllids on LillypillyPimple Psyllids on Lillypilly
Most gardeners will be familiar with the twisted, puckered growth these sucking insects cause on lillypilly plants. The insect attacks the new foliage and in taking up residence on the leaf, create a pimple-like bump under which they can hide. If you look closely you can often see the insect, however even when the insect departs, the lump remains. Very few lillypilly trees are immune to this pest (but Syzygium 'Cascade' is one of them). Select lillypilly varieties carefully. Prune foliage from affected plants, then spray the new growth with a botanical oil (Eco-Oil or Eco-Neem) and repeat this spraying whenever plants make significant new growth.

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. Rat's are typically also to blame if you see passionfruit with a neat circular hole in the shell and an empty fruit.

SawflySawfly Larvae
The spitfires or sawflies that feed on eucalyptus foliage are not flies, but wasp larvae.  Adult wasps pupate in the soil (often for years) and emerging in spring and summer. At this time the females use a modified egg laying structure to ‘saw’ into the leaf to lay eggs (often parthenogenetically – without the need to find a 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.

Fortunately, most native plant species they attack seem to be able to 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 will also cause them to drop off.

Scale and AntsScale
Several scale species 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) are commonly found on established citrus trees, but also affect ornamentals such as gardenias, lillypilly hedges and rainforest trees. Scale insects are commonly associated with ants who harvest honey dew exudate produced by the scale and sooty mould fungus that grows on the honey dew. Oil sprays will control scale and sooty mould. You will need to apply two to three applications at monthly intervals. This will control new generations of scale that emerge from beneath the body of mature scale killed by initial applications. See White Rose Scale below. 

Scale on Grass Trees
Are your grass trees looking a bit sad? Take a really close look down in the centre of the head of foliage to check for scale insects. This specimen is particularly badly affected, but often the problem is well hidden. Oil sprays, pyrethrum and insecticides are not very effective. The natural solution is fire. Use a small gas blow torch or the type you use in the kitchen to caramelise sugar (as in creme brulee) to simulate a bush fire and burn the head of the plant and toast the scale!

SnailsSnails and Slugs
Everyone seems to have a home made remedy to control snails and slugs. Saucers of beer are supposed to attract them, but in my experience the beer must be home made for it to hold much appeal. Non-toxic iron-based baits are the safest of the snail and slug pellet 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 (for iron and copper products see Green Harvest on the [Links] page). Poor the leftovers from your coffee plunger over areas where snails and slugs congregate. They hate caffeine!.

Sod web worm moth
This is webbing from the sod web worm moth. It is a type of caterpillar (Herpetogramma licarsisalis)

Spined Citrus BugSpined Citrus Bug
These insects look like they are wearing pointed shoulder pads. When young they vary in colour, but adults are leaf green and 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 appear particularly susceptible. Wear gloves and pick them off by hand or use a leaf blower or vacuum clearer to suck them up. Oil spray (botanical oil, Eco-Oil or Eco-Neem) or pyrethrum can be effective, but needs to be applied directly to the insect. You need to control these pests as even a small infestation can do considerable damage to your harvest.

Thrips are slender black or grey sucking insects that commonly attack flowers and developing fruit. There are hundreds of different types. Their feeding activity can cause premature flower drop, failure of flowers to set fruit, flower deformities and twisted, puckered or malformed fruit. 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. It will be rare to see thrips on damaged fruit as the insects will have been present and created the problem when the fruit first formed. To control thrips, treat the developing flowers regularly with either soap sprays, wettable or dusting sulphur. Oil sprays can be used on ornamentals or other plants whose foliage is suitably hardened. Plants commonly affected include beans, tomatoes, onions, gardenias, azaleas, roses, bulbs and native plants. Many beneficial insects prey on thrips providing natural biological control. 

Thrips on Gardenias - See above

Tomato Russet MiteTomato Russet Mite
If your tomatoes seem to start to grow well, then gradually begin to develop dry foliage and smooth, bronze stems that progress from the lower leaves upwards within the plant, you should suspect tomato russet mites. Invisible to the naked eye, these pests are very common and result in plants that gradually become weaker and more naked.

Spray each week with wettable sulphur, soap sprays like Natrasoap or products like Eco-Neem taking care to thoroughly wet the undersides of the foliage and the stems. If you have had this pest in past crops, take a preventative approach and begin spraying when you first plant new seedlings or when you seeds germinate.

Rose ScaleWhite Rose Scale
Infestations of white rose scale can be particularly debilitating to rose plants, eventually killing plants completely if left unchecked. Where infestations are particularly heavy, warm soapy water and a soft scrubbing brush can be used to remove the majority of the scale. A follow up application of an oil based spray, see [homemade remedies-Oil Spray] will usually bring about control. Repeat as often as necessary. Remember to fertilise affected roses to compensate for the loss of vigour that will undoubtedly result from the scale infestation. White rose scale often multiplies rapidly during winter.

Webbing Caterpillars
This webbing is caused by a caterpillar (there are several different types of webbing caterpillars). It makes this nest to hide itself from birds and other predators. If you are brave enough to pull the webbing apart you will find it hiding inside. You can cut off and dispose of the affected branches - they often affect the tip growth of bottlebrush or small internal branches of paperbarks (Melaleuca) and teatree (Leptospermum). Alternatively, just remove the webbing by hand when you see it. Plants recover quickly.

 I always think of weevils in the garden as being interesting, rather than harmful creatures. They 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. They will chew a few leaves, but control is rarely warranted.
Please note: These are not the weevils that you find in flour or grains stored in the pantry. Pantry pests are typically the larvae of moths (Plodia interpunctella or Kuehniella species), the larvae of which are also sometimes called weevils. Pantry moths do not come into the pantry from the garden, they are in the products when you buy them.  Place your flour and other grains in the freezer for 48 hours before storing them in sealed containers in the pantry or store permanently in the refrigerator.

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