My summer reading is Wasp and Bee Management on Grapes by Jody Gangloff-Kaufmann, PhD, NYSIPM Program, Cornell University. I like the bit at the end where the wasps swarm around a bit of fish suspended over a bucket of soapy water, fall in and drown. One heading Bald-faced Hornets are Aggressive has also stayed with me. Things grape-growers should be concerned about include yellowjackets, paper wasps, the bald-faced hornets, European hornets, and bumble bees. All I know is that we get avispas (wasps) and algo como avispas (something like wasps) and a lot of bees which can have the grapes if they want them (Save The Bee).
I really don’t like killing things however this farm with its water, fruit and vineyard is an ideal habitat for human beings and wasps alike and, despite my best efforts to be tolerant, we don’t rub along.
Late at night, I’ve knocked a lot of nests down from under the roof tiles but over the last week the buzzing in the trees nearest to the vineyard has ratcheted up, a sign no doubt that the grapes are sweet and ripe. So I’ve been studying the methods of getting rid of them. So far I have tried:
Plastic bottles part-filled with lemonade suspended from branches. Wasps go in through holes punched in the side, get sticky and don’t come out. I tried cutting off and inverting the top third of the plastic bottle to make a funnel entry but felt sorry for myself spending so much time on such depressing craft.
The bucket, soapy water and suspended fish – or ham – method, although attracting meat-eating wasps to the farm is something straight out of a Far Side cartoon.
Inflated paper bags dangling from vines and fencing. Wasps think they are the nests of a rival faction and leave. This fails here not, as I first thought because these wasps are especially bright, but because they are not the species that make nests that look like paper bags. The bags mean nothing to them.
I bash nests down at night using a stick, stamp on them and run away. A website featuring organic tips suggests removing nests, putting them in plastic bags and shoving them in the freezer. This seems complicated and psychotic.
The jam jar trick in which I cut a small hole in the lid, smear the underside with jam, pour a little orange juice or beer in the jar and screw the lid on is clean and classic.
Howard Russell of Michigan State University Diagnostic Services says ‘small, exposed paper wasp nests are easily controlled by aerosol wasp sprays that produce a concentrated stream of juice that has a range of 15 to 20 feet. Point the nozzle at the nest, shoot and watch ‘em die‘. It was while trying this that I realised that I do not have paper wasps.’Paper wasps do not cover their nests in a paper maché envelope like those of yellowjackets and baldfaced hornets, so their brood cells and workers are exposed and vulnerable’ says Howard. The ones I have do and they are not; they come out fighting.
In Attracting Insects’ Natural Enemies, a product of Cornell University, advises pulling up Queen Ann’s lace, parsley, dill, dahlias, daisies, asters, cosmos, tansy, and yarrow and to plant stuff that wasps find repellant such as wormwood, eucalyptus, mint and citronella. I like this ground-up approach, but it’s going to take me a long time to grow eucalyptus.
Finally, ‘hang a sandwich filled with water,’ is advice I read on bestplants.com: ‘This will make the wasps think there is a spider web on your door which can trap them.’ No matter how many times I study this, I can’t begin to imagine what it means.