You must have noticed them. The yellow-and-black striped European Wasps zooming around our district, hanging around food and chasing us indoors. Hopefully you haven’t been on their pointy end, as individual wasps can sting several times, each time worse than a bee. They can also swarm and deliver many stings at once.
The wasps are attracted to sweet food and meat, so cleaning up and sealing rubbish will discourage them. The wasps will fly straight from their food to a nest, making the nests fairly easy to find.
Nests are usually small holes in the ground, about 4-8cm wide. Nests can house up to 100,000 individuals which stream in and out all day. Stay well back because if a nest is threatened, the wasps release a chemical which triggers the colony to attack the threat.
Maybe it was the moist summer, and perhaps the great apple season which has left fruit rotting around the trees. Whatever the reason, there are more of these wasps now than in the past. The local pest controller says he previously only had 1-2 call-outs for nest removals in a year, but he’s getting 3-4 a week at the moment. Braidwood Rural got 5 cans of wasp spray in last Friday and sold out in a single day.
Keep on the lookout for nests. If you find one, the best and safest option is to find the local pest controller in the Community Directory and arrange for him to destroy the nest. Autumn is a critical time since now the queens and laying eggs for the next generation of queens. Every nest we kill now could reduce the problem significantly for next year.
The Museum of Victoria publishes tips for “Do it yourself European wasp extermination” at http://museumvictoria.com.au/wasps/wasp_control.asp, and like me, takes no responsibility for injuries incurred using the information. But I’ve destroyed some nests, and talked to many others around town who have done it too, so here’s what I’ve learned.
* Don’t risk it if you are allergic to wasp stings,
* Make sure someone knows where you are and what you are doing.
* Treat the nest at night when activity is low,
* Wear loose clothes and fully cover your body, head, eyes etc,
* Put red cellophane over a torch, because they can’t see red light, and don’t alert them by shining it right at the hole,
Locals are having success with several different treatments. The pest controllers are licensed to use a high strength powder which will knock out a nest in one go. Other premethrin, propoxur or carbaryl dusts are available, although not in Braidwood. Both local rural suppliers carry propellant cans of wasp killer. Petrol is another option, and though the experts advice is that it doesn’t work well, it did the trick on my nests. Either pour 1.5L down a nest on two consecutive nights, or soak a rag in petrol and plug the hole with it. The fumes kill the wasps, so don’t light the petrol. Check treated nests in the following days, and be prepared to retreat to finish the job.
The Department of Primary Industries has a fact sheet at http://www.dpi.nsw.gov.au/agriculture/pests-weeds/insects/to-be-adjusted