The Trouble with Wasps…

Anyone who’s ever eaten outside in the summer will know that wasps can be a problem. The wasps we see most are the social wasps (Vespula species); the ones that make large nests, generally where you don’t want them. A few years a ago I had a nest in my compost heap. I didn’t empty out the compost until they’d gone, and it was only then I discovered they’d excavated a hole the size of a bucket. Sometimes when I went to the compost bin a wasp would fly out of the nest entrance straight into my forehead, bounce off and then carry on around me, but they never really bothered me. But if they identify you as a threat, then you’re in trouble!

Comings and goings at the nest entrance

There’s currently a nest in ‘the hill’ – the mound of earth and rocks behind the pond. The hill is due to be removed, as it doesn’t feature on my garden design (a free-draining rockery with alpine plants doesn’t sit well by a pond), but I’ll probably not get around to that until after the nest has been vacated, so the intention is to live and let live. I’ve only been stung once so far. Apart from trying to help themselves to our lunch, they haven’t been too much trouble. But I’ve been removing a large and decrepit patio, and one day the vibrations from my pick axe must have disturbed them, because the next moment I’d dropped the pick axe and was running back to the house, waving my arms about like an idiot.

My RHS Pests and Diseases book tells me wasps can be a significant pest because they eat fruit – apples, pears, plums and berries. It doesn’t mention that they also eat rose buds. I first noticed this while volunteering at Dyffryn gardens in the Vale of Glamorgan. In my garden there are currently only two roses. The red climbing rose by the chicken run has escaped unscathed, but the yellow rose, which is currently by the compost heap (but due to be moved soon) is closer to the nest. In June and July the blooms were fine. But then the wasps started to munch on the buds. Ever since, very few buds have made it to be flowers, and those that have are raggedy.

One of the roses that made it – not much to look at.

The book also says that wasps are important predators of garden pests (illustrated by a nice picture of a wasp carrying off a vine weevil). Which is fine as far as it goes, but I know wasps don’t just kill pests, but beneficial insects such as pollinators too. In fact, they’re the only insect I’ve seen killing for reasons other than to eat. I once had an old ivy tree that was a magnet for insects when in flower. One year the whole of the crown was alive with flying insects. On closer inspection I saw a scene of carnage, because the wasps, rather than share the feast with bees and hoverflies of all kinds, had decided to see off the competition. It was a mini massacre. Each wasp would grab its victim – be it hoverfly, honey bee, bumble bee, etc. and sting it repeatedly. Killer and victim, neither able to fly while in the deadly embrace, would fall to ground together. After a short moment the wasp would rise up to look for it’s next target, leaving the unfortunate victim in it’s death throes. The ground became thick with dead pollinators.

I have to admit to a grudging respect for wasps – in a world where the fittest survive, they are far and away the fittest. Solitary wasps, many of which are plain black rather than with the danger-warning yellow stripes, are just as tough. In my last garden I would regularly see them fly down, grab a woodlouse spider (which is a fearsome looking beast and, apparently, one of the few British spiders with fangs that can pierce human skin), casually sting it to death and then carry it off to its lair. Parasitic wasps lay their eggs inside the bodies of other organisms (such as caterpillars). When the eggs hatch out they feed on the poor creature’s insides; literally eating it alive. Everything’s got to live somehow, I know, but to me, that’s just plain wrong!

Wasp nests tend to finish in the autumn – having sent out new queens to find places to hibernate, the rest of the wasps die. I’m hoping that will happen soon with our nest, so I can get on with the work around the pond.

text & photos © Graham Wright 2020