PREVENT FRUIT FLY

More areas than ever before are being affected by fruit fly. Last summer, fruit flies found their way into parts of South Australia, Victoria and across Bass Strait to northern Tasmania. Even if you live in a normally fruit fly-free zone, keep a look out for these pests. Hanging up a trap and checking it regularly is a good way to do this.

As the weather warms up, fruit flies emerge from their winter hiding places and start to breed. Summer fruits, especially nectarines and peaches, and the soft fruiting vegies such as tomatoes and capsicums, are their favourites. Now is the time to protect vulnerable fruit.

Make fruit fly traps out of plastic bottles, with holes drilled near the top and a fly-killing attractant in the base. Recipes abound, but usually combine sugary or yeasty ingredients mixed with an insecticide. Commercially available pheromone traps (such as Dak.pot Lure and Insecticide and Fruit Fly Trap) that attract and kill male Queensland fruit fly are effective over a much bigger area and can be useful to indicate fruit fly activity. It’s the egg-laying females, however, that damage fruit, so for overall control it is necessary to control females. Cera Trap lures both male and female Mediterranean fruit flies (found in WA). The insects can’t escape once they’re inside, eventually drowning in the fluid attractant.

Other control measures use baits based on the female fruit fly’s need to feed on protein before she lays eggs. Most of these are ‘splash baits’ such as Eco-Naturalure, which are applied near, but not on, fruit. The fly feeds on the protein and, at the same time, ingests the fatal insecticide. Splash baits must be reapplied after rain or after they have dried out. Insecticides used in baits include biologically friendly products such as spinosad.

Once the pollinated fruit begins to grow and ripen it can be protected by