Horticultural pest and diseases
By Denis Crawford
Think weevil, think pest? Think again. Weevils are incredibly diverse, and some species are plant pollinators.
With about 400,000 species worldwide, the insect order Coleoptera (beetles) accounts for about 25% of all animal species on earth. 20% of those beetles are weevils of the superfamily Curculionoidea.… Continue reading
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Tiny Trichogramma wasps are mass reared to control caterpillar pests (image supplied by Denis Crawford)
By Denis Crawford
There is a long and fascinating history of mass rearing of various insects, and it seems that the practice is set to expand somewhat.
There has been a lot of press in the last couple of years about farming insects for human consumption.… Continue reading
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Insects that have life cycles of complete metamorphosis have larvae that come in a variety of forms.
A life cycle of complete metamorphosis (holometabolous) means hatching from an egg into a larval stage, then pupating, and later emerging as an adult.… Continue reading
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This caterpillar has three pairs of true legs and four pairs of abdominal prolegs (Supplied by Denis Crawford of Graphic Science)
Many insects are instantly recognisable but what do you do when you find an insect you’ve never seen before?
If I described an insect as having a triangular head with large eyes, spindly hind legs and grasping raptorial forelegs, I reckon most of you would have an image of a praying mantis in mind.… Continue reading
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Many ants are beneficial, but some ant species can be pests in some situations. When is that?
This Pest Files is inspired by some recent encounters I had with ants. In late January 2023 I noticed several species of ants climbing the trunk of a young roadside gumtree (Eucalyptus obliqua).… Continue reading
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Biological control may not be an instant pest solution, but it is a pest control option well worth pursuing.
Large parts of eastern Australia have just been through a very wet spring and early summer. That period of warm wet weather meant a boom time for mosquitoes, they were everywhere in huge numbers.… Continue reading
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The arrival of an exotic herbivorous insect in an environment dominated by only a few plant species can be a recipe for disaster.
When an insect is introduced into an area with few natural pathogens, parasites and predators, that insect may become a severe pest.… Continue reading
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Given the recent debate in the media about the future of pesticides in some parts of the world, it’s time to look at the alternatives to pesticides.
A recent series of articles in The Guardian“Toxic nation: Australia’s pesticide problem” highlighted several issues with pesticide use in Australia.… Continue reading
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Tiny wasps that are barely visible to the naked eye are important biological control agents for various pests. If the wasps are so small, how do you know they are present?
I recently did some photography for a Queensland integrated pest management company that needed photos of Trichogramma pretiosum, a tiny wasp less than a millimetre long.… Continue reading
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I wrote an article in March 2009 titled ‘Why do we have pests?’ The main themes of that Pest Files were monoculture, invasive insects, suppression of beneficials, and resistance to pesticides. What has changed in the last 13 years?… Continue reading
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