Bugs, Grubs, and Insects

There are numerous creatures out there that will eat your crop and harvest, they will get to your ripe tomato before you, they will hide under leaves while sucking away your crops life, and they can be so small that you don't even notice that they're there! I always suspect that anything and everything is in your veggie garden or crop and it comes down to knowing when and where to look and whether or not there is any action necessary. For someone who is new to the world of bugs, this will provide a little insight as to what you may find on you indoor plants, veggie garden or farm. After reading this article, I hope you'll be equipped with being able to identify when something is not right and having the capacity to look into it further and find yourself the solution you need.

Caterpillars
Grubs! the easiest to spot and the most destructive visually. They come in different sizes and colours but can be the easiest to identify. Signs on plants will be the classic holes in leaves and fruit, and edges of leaves missing. Grubs are deposited on the plant via an egg from a moth or butterfly which is a pretty good sign that your plants are going to be attacked. The eggs of a cluster caterpillar can be easily distinguished from the rest from its web like cluster but most moths will lay their eggs in small bunches, in lines, patterns, or singularly on their preferred food source which can be hard to find.

Mealy Bug
The most common indoor plant pest! Often found in cool shaded areas and appear to be a white fluffy growth on the plant but are in fact sucking pests drinking the life out of your plant. Mealy bug can be easily controlled by spray options such as an organic oil or chemical, or placing the potted plant in a sunnier position which will dry off and kill the mealy bugs that are not hidden. As mealy bugs feed they produce a honey dew which can cause sooty mold to grow which is black and can cover large portions of the plant. Black sooty mold doesn't damage the plant directly but will stop sunlight reaching the plant.

Mites
Tiny spiders, some you can see with the naked eye and others you'll need a microscope or magnifying glass. Mites are sucking pests and there are a range of them in Australia known as the two spotted mite, red legged earth mite (RLEM), Bryobia mite, and russet mite. The most common mites are RLEM and the two spotted mite which are visible with the naked eye and cause damage to plants that appear as white specks on the upper surface of the leaf. Grasses are generally tolerant to these pests but broadleaf crops such as canola, tomatoes, hemp, lupins, melons, and beans can experience in severe cases a total loss of crop. Mites, along with caterpillars are a big pest to keep an eye out for because of the cost they will cause. To control these mites there are plenty of spray options, organic or otherwise, there is also a company in Australia that reproduce bugs that eat these mites as well! Rotating to grass crops or broadleaf crops resistant/tolerant to mites is also a good option for reducing mite numbers and avoiding resistance if you're a grower looking for years of crop production without resistance issues.

Aphids
Melon aphid, russian wheat aphid, green peach aphid and cotton aphid are sucking pests that are visible to the naked eye and cause damage not just from feeding but from the toxins they can produce and put into the plant while feeding. Like mites, aphids have the ability to gain resistance to chemical spray options making this more costly for farmers who do not rotate their sprays and controls. To identify if your plants have aphids simply inspect them, for grasses look down the centre of the plant as they are usually hiding between the leaves where they join the rest of the plant, for Broadleaf plants they're usually found on the youngest leaves or the growing tip of the plant. There are also organic sprays option for aphids and bugs sold that eat aphids as well such as lacewings. Aphids also have the capacity to spread viruses around such as yellow zuchini mosaic virus and cucumber mosaic virus. Fortunately, there are ways for preventing these viruses and minimising their damage.

Thrips
These insects can be smaller than mites, are hard to find but fortunately generally don't cause too much damage to warrant action. They are another sucking pest and are difficult to find due to their size but can be relatively easy to find. If you're growing a plant that has small flowers such as a tomato, melon, or pepper plant a good trick to finding how many thrips you have is by picking a flower off the plant and face the opening down into your palm, you then knock the back of the flower to try and dislodge any thrips that may be hiding in there, if there are thrips then a few may fall out and look like skinny long specks moving along your hand. However, not all thrips are bad, you have the thrips such as the Western Flower thrip which eat crops and are a pale yellow colour but there are also predatory thrips as well that don't eat plants! You'll need a microscope to be able to identify the thrips though.

Nematodes
These are worms, some a good such as the ones that you can easily find in organic rich soils and the worm farms but there are also nematodes that can not be seen with the naked eye and are called lesion nematodes or the root knot nematode. These crop eating nematodes are found throughout the world in areas where the winter is short, they prefer warmer weather and sandy soils but will cause crop loss in heavier clay soils as well. It can be easy to identify if you have nematodes or not, especially the root knot nematode which will leave bumps or knots on the roots of your plant, giving its name the root knot nematode. You will only identify this issue by pulling the plant out of the soil and inspecting the roots for these lumps/knots which some growers will call potatoes because of how similar it can look. To control the nematodes there are various soil drenches and sprays available, otherwise you can fallow but this will require you to stay on top of your weeds to reduce the feed available to the nematodes, you can also grow nematodes resistant varieties such as sorghum, and lastly you can grow "trap crops" which is where you grow a crop that is preferable to the nematode and then destroy the roots with a rotary hoe to kill the nematodes or their food source to reduce their population, this may not be a proven practice, however.

Locusts
Grass hoppers, leaf hoppers, jassids or locusts can cause substantial damage to your crop through the quantity of leaf area they can damage which will stunt the plant or in worse cases kill it. This can be controlled by using netting, green housing and various sprays but luckily this not a frequent problem unless there is plague numbers such as a swarm moving through the area which should be monitored if you're trying to produce large quantities of harvest.  Orchids can handle moderate damage as the trees will generally have large stores of carbohydrates in the stems and branches and will flush out new leaves once this occurs. Not a common pest but still one to keep in mind, the damage is easily identified as they will eat the sides of the leaves as their mouths don't allow them to start from the centre of the leaf unless there is already a hole there to begin with.

Whitefly
This insect is the size of a small fly and as its name gives it, has white wings with a body that looks to be covered in a fine white dust. This insect has the potential to spread viruses too, depending on where you are, and is another sucking pest. They can be found when a plant is disturbed and they fly around. High numbers are generally required for them to cause significant damage but depending where you live, their numbers can breed up quickly. There are plenty of options from chemical or organic sprays to beneficial bugs that can be used to control whitefly.

To Conclude...
This article is only a glaze over the common pests you may find around your home or on farm. In Australia we are privileged to have government bodies such as the department of primary industries and regional development (DPIRD) and other government bodies in states such as New South Wales, Queensland, and South Australia who can provide in-depth information on these pests along with professionals who are available with a flick of an email or phone call. Take advantage of these departments and this page to solve your problems or to identify the good bugs.

Happy growing!