Aphids
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 [Do It Yourself Pest Control-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.

Azalea 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.

Borer
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]

Bronze 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, botanical oil sprays (Eco-Oil and Eco-Neem) are also effective, especially on nymph stages.

Cabbage 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 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 'Do It Yourself Pest Control'].

Case 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.

Citrus 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.

Lily or Crinum 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 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 'Do It Yourself Pest Control'], use tea tree based products like Eco-Grub or spinosad sprays like Success . Repeat applications may be required during spring, summer and autumn.

Dodder
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 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-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.

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.

Ladybird (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. 

Leaf 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.

Lerp
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 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 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. 

Mites
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 mites. Fine webbing 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.

Pimple 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.

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
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. 

Snails 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!.

Spined 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
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. 

Tomato 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.

White 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 [Do It Yourself Controls - 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.

Weevils
 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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