The RHS is sticking to it’s story that wasps are beneficial insects…
From my own observations I would say that any positive contribution to the garden (and possibly the wider environment too) is outweighed by the harm they do. Firstly, they eat beneficial animals as well as pests. What’s more, they will kill anything that gets in their way. I’ve witnessed the mass murder of hoverflies and bees, with deaths in the hundreds, apparently because the wasps won’t tolerate competition for nectar from the plants they visit.
My own observation suggests wasps are not significant pollinators – more likely to eat flowers than to pollinate them (particularly roses). They were certainly nowhere to be seen when my fruit trees were in blossom, so did nothing to help generate the copious amounts of apples, pears, plums and damsons that formed. But now, before much of the fruit is even close to ripening, they’re systematically destroying the harvest…
The RHS says ‘damage to plants is limited, and mainly occurs in late summer…’ Limited’? They should see the state of my apples! And it’s not late summer yet. Maybe they’re out earlier because of the warm, dry weather in June (remember that?)
The same happened last year. I’ve taken action, through the organic method of using traps – glass jars with a piece of paper over the top, with a wasp-sized hole in it. The idea is the wasps go into the jar to get to the treat inside, and end up drowning in it…
The RHS suggested using a mixture of jam and water, and I’ve found this works well. The first jar caught perhaps fifty wasps. I tried beer, but while it caught some wasps, it was more attractive to flies and moths. For the latest refill, I’ve used a mixture of beer and jam (the wasp version of alco-pop?) As you can see, I’ve used foil, rather than paper, as it’s waterproof. There’s some question as to whether these traps actually attract more wasps, but I felt I had to try something, or there won’t be any apples left.
It wouldn’t be so bad if they chose one apple at a time, but of course, they wouldn’t dream of being so considerate. Instead, they burrow into numerous apples at a time which, in no time, start to go rotten before the wasps have made more than a small hole. At which point, they move on to fresh apples. So you can see, the entire crop is at risk.
‘Expert’ opinion generally seems to be that wasps will only sting if threatened. The trouble is, they seem to have a very low threat perception threshold. Get too close when they’re in the act of stealing your food (whether from your plate, the kitchen, or the orchard), and you’re seen as a threat.
Wasps are aggressive, irritable creatures, with a vindictive streak. Last year we were inundated with nests. The patio at the end of the garden was a no go area. We took our lives in our hands when we took garden or food waste to the compost. And even if we were lucky enough to get in or out of the front door without being stung, opening the door would let another half-a-dozen or so into the house. Eventually we succumbed, and called in the council pest controller.
I will just say (and I probably should have said it earlier), that not all wasps are the same. It’s the so-called ‘social’ wasps – Vespula species (otherwise known as ‘yellow jackets’) – that are the troublemakers. There are many species of solitary wasps which are not so troublesome. You wouldn’t want to be their prey mind. Many of them inject their eggs into the prey (often a caterpillar). The eggs hatch out, and the wasp larvae slowly eat the host from the inside out. While it’s still alive! That said, they don’t, as far as I’m aware, cause damage to plants, or harass us humans. Their pest control activities make them useful garden predators. Although many will eat spiders, which are very much a gardener’s friend. But then, no-one’s perfect…
text & images © graham wright 2023
