Insects

Planting for pollinators: Button Wrinklewort as a case study

Lasioglossum lanarium visiting Button Wrinklewort flower
~ Ben Courtice ~ Leave a comment

Since honeybees have started coming into trouble, there has been a bit of popular attention paid to the vital role of pollinators in agriculture. Of course, there are many bees besides the European honeybee, which has unfairly hogged the limelight. Many of our native insects are also valuable pollinators. Having said that, we know a lot more about honeybees than we do about most of the others – it is estimated that there may be about 2000 bee species in Australia, but many are undiscovered and undescribed and certainly un-studied.

Whether it’s for maintaining pollination services to agriculture, or simply maintaining biodiversity in wild populations, we have a lot to learn so it was quite exciting to be able to learn about a couple of native bees in their natural environment doing my honours research in 2017-18. I was actually researching the ecology of the Button Wrinklewort, an endangered daisy species, but it involved studying insect visitors to the plant and making inferences about pollination from my observations. You can read the full paper in the Australian Journal of Botany if you wish (it’s paywalled, sorry), but I’ll reproduce the abstract here: Continue reading →

Planting native grass to control mosquito borne disease

Yellow robin
~ Ben Courtice ~ 2 Comments

Did you know that if you want to control mosquito borne disease it may help to plant native grasses? The reasoning as to why this might be so is a bit of a yarn. Bear with me.

Living near a river, mosquitoes are inevitable, but some times they are worse than others. And they are a worry, as mosquito-borne diseases like Ross River Fever and maybe even the sinister “Buruli ulcer” are becoming more common even in Melbourne.

Microbats, those little flutterers that are about the size of a mouse (“flittermice” is an old name), eat about half their body weight in insects every night. Including mosquitoes. Up to 500 insects an hour. But the bats need somewhere to hang out and sleep during the day, and this is typically in little crevices and hollows in old trees. Continue reading →

Keeping ahead of harlequin bugs

~ Ben Courtice ~ 2 Comments

EDIT (March 2018): the following advice works, I believe. I observe plague proportions of these bugs destroying fruit in nearby gardens, while my yard has only a few of them wandering around without causing much problem. I mention removing mallow weeds; I’d remove all tall weed patches around the garden, and if you border on a vacant lot, maybe a strip along the side of it as well. Living weeds and tall grass seem to provide vital harbour even when they aren’t also food.

With a brief moment of warm weather on September 2 this year, the harlequin bugs are on the march again.

Many gardeners around Bacchus Marsh have encountered plagues of these sap-sucking critters. They are remarkably adaptable, feeding off hosts as widespread as mallow, pepper tree, citrus, tomatoes and rhubarb. Most insects that are leaf-chewers only feed off one or a few closely related species of plant, because they need to specialise their metabolism to overcome the chemical defenses of the plant. Sap-suckers bypass the leaf with its battery of noxious compounds, and tap straight into the sweet flow of the plant’s sap, which is relatively free of chemical defenses. Continue reading →

Manna from Mallee

Lerp on Eucalyptus behriana
~ Ben Courtice ~ Leave a comment

It’s been a while between posts and there has been a number of things I have meant to write on. Maybe I’ll catch up soon. But on the weekend I went for a walk in the “Melton Mallee” – Long Forest nature conservation reserve, that is – and I’ll share a few interesting things I saw.

I was there on a hot day, which I find is a great time to be out in the bush. The light is strong and really brings out the bright greens and bronzes of Eucalypt leaves and trunks. The sparse shade is all the more welcome, and the big sky stretches above. Not too many animals are out in the heat of the day, and it’s quiet enough to hear those that are. Continue reading →

Harlequin Bug Hell

~ Ben Courtice ~ Leave a comment

The Harlequin Bug, Dindymus versicolor, is a native Australian insect that can become a pest in gardens and agriculture.

You can buy poison to kill it; I wouldn’t put poison in my garden if I can avoid it.

For ornamental plants, the commercial product Confidor is available; its active ingredient is Imidacloprid, a neonicotinoid – a class of chemicals now banned in some countries because of their suspected role in colony collapse disorder of bees.

Heidi, the blogger at A Year In A Gippsland Garden, relays the recipe from Gardening Australia’s Peter Cundall: a strong mixture of cheap (hopefully, biodegradable) detergent in water. Spray it on the bugs, or knock them into a bucket of it.

image
(photo from A Year In A Gippsland Garden – visit that blog for more excellent pics and discussion)

How to get it out of your garden by other means? I looked for scientific papers and there isn’t much, but here’s what I found.

Control of mallow/hibiscus species (like the weeds that commonly grow in my lawn here) seems sensible, based on a paper from Latrobe University, published in the Australian Journal of Ecology in 1981 (see table reproduced below). Continue reading →