Aphids
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Rose aphids on new growth
Aphids are a common pest of a wide range of plants, including roses, fruit trees and vegetables.
Aphids can build up in number at astonishing rates under the right conditions. Adult females can produce live young without mating, which allows even a small number of adults to rapidly build to a serious infestation. A single female aphid can produce literally hundreds of young in a few days.
Aphids can cause damage in several ways. The most obvious is the high level of sooty mould that results on foliage around the aphids. The sugary solution the aphids release during feeding promotes the growth of this unsightly black mould. If bad enough, plant health will also suffer from reduced photosynthesis, and plant death can result.
Aphids can also cause direct distortion of growing tips, fruit and flowers, and can even defoliate your plants. Aphids can also act as carriers of a range of really nasty diseases of several plant species.
Monitoring
Check fresh growing tips for the presence of aphids. Often the very young aphid ‘nymphs’ will be difficult to find, as they will sit in folds of leaves and foliage.
It is important to find these low numbers of aphids, as populations can explode if left unchecked for even a few weeks.
Control Options
There is a range of pesticides available for the control of aphids, including “soft” options such as white oil. These sprays need to completely cover all pests, and have no ‘residual effect’, allowing aphids to build up after the spray has dissipated.
Toxic chemicals will have more control, but re-infestation can easily occur again, as the pesticide will also kill all of the predators and parasites, and a vicious cycle of infestation and chemical applications will start!
Predators and parasites offer a better alternative, with longer lasting and cheaper control achieved.
Lacewings – Aphid Predator
Adult Lacewing
Lacewings consume a wide range of common pests, and they are particularly effective against most aphids. The Green Lacewing is a native to Australia and is found throughout all states.
The advantage of using these predators is they do the work of finding and killing the aphids for you. The need to apply a spray to every surface of every plant in the garden is time consuming. Using lacewings to do this for you gives you more time to actually enjoy your garden!
For further information on this or other pests and how to control them, email questions@bugcentral.com.au
