As Australians, we take pride in our lush gardens and thriving orchards, which not only beautify our homes but also provide us with fresh produce. However, a new threat has emerged that could devastate our beloved green spaces in no time. The monolepta beetle, also known as the red-shouldered leaf beetle, has been wreaking havoc across New South Wales, leaving a trail of destruction in its wake.
These tiny beetles, which were once a rare sight for many, have now multiplied to ‘plague proportions,’ particularly affecting areas down the NSW Central Coast, Hunter Valley, and Sydney regions. The infestation has spread as far south as Camden in Sydney’s southwest, causing alarm among gardeners and farmers alike.
Tim Pickles, a seasoned horticulturalist and owner of Tim’s Garden Centre in Campbelltown, has been in the business for over four decades and was taken aback by the sudden invasion. ‘They’re in plague proportions, you can’t believe how many there are. There’s thousands, as soon as you bump them they all fly into the air and then they settle again and start eating again,’ he told Yahoo News.
The monolepta beetle’s southern migration is considered ‘somewhat unusual’ by experts like Dr Kayvan Etebari, an entomologist and senior lecturer at the University of Queensland. He suggests that recent weather conditions, such as warmer temperatures and increased humidity, may have created ideal breeding conditions for these pests. Additionally, the availability of food plants and natural dispersal could be influencing their movement. While this could be a temporary occurrence, it might also signal a broader environmental shift.
The impact of these beetles is not just a visual blight; they pose a serious threat to the health of plants. ‘They skeletonise the leaves, they eat holes throughout the leaves. So basically it ends up looking like a tea strainer. Then they eat all the flowers, they destroy the flowers so they don’t open,’ Pickles explained. The speed at which they decimate gardens and orchards is alarming, with reports of entire areas being destroyed overnight.
One orchard owner near Taree in Bootawa described the situation as ‘the worst I have ever experienced,’ with her trees being destroyed by the beetles in a single night. From apricot to avocado and citrus trees, nectarine gardens, and vegetable patches, nothing seems to be safe from their insatiable appetite.
The financial implications for farmers are dire. Dr Etebari notes that these beetles can lead to defoliation, reduced photosynthesis, and compromised plant health. In crops like soybeans, mungbeans, and navy beans, severe infestations have resulted in significant yield losses. For example, maize crops have suffered up to 40 per cent loss due to the death of young plants.
So, what can you do if you spot the monolepta beetle in your garden? The key is to act swiftly. For trees and non-edible plants, spraying with pyrethrum is recommended, but it’s crucial to do this at dusk or after sunset to protect the bees. ‘You don’t want to spray during the day because you’ll be killing the bees as well,’ Pickles warns.
Dr Etebari also advises gardeners to regularly monitor for signs of damage, remove weeds and alternative host plants, and consider using barriers like mesh netting. If necessary, apply registered insecticides carefully to target infestations only.
While the current influx of monolepta beetles is concerning, there is hope that this won’t become a regular occurrence. ‘The population of monolepta beetles can fluctuate significantly from year to year,’ Dr Etebari explains, offering a glimmer of hope that these pests may not be a permanent fixture in our gardens.
Have you come across these beetles in your garden? What tips or strategies have you found effective in dealing with garden pests? Share your experiences in the comments below, and let’s work together to keep our gardens healthy and thriving!
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