Is there a wasp nest in this tree?

Question

We have a small tree in the border of our back garden. I noticed today that there is a constant sparse crowd of wasps around the base of the tree, if you stop and look then there's easily a dozen in sight at any time. The base of the tree has a thick carpet of ivy around it, and there are a couple of neglected lanterns on the floor and hanging in the tree. The tree has no flowers and there are none around it. I know the difference between wasps, bees, hoverflies, and beeflies.

I wonder if this crowd is likely because there is a nest in the vicinity. I haven't gone prodding around in the ivy, branches, or lanterns, because - well, wasps! We have a small inquisitive dog, and I'm thinking of trimming back this tree and another near it so there are reasons to be at least slightly concerned.

(UK, Southwest, late August)

Answer 1

Can't tell much from your photos; I think you need a closeup of the area with the wasps in the photo, if possible. In the US, we do have wasps that nest underground; the ones I'm familiar with do like to nest within other plants (in one case, the exit hole was at the base of a large purple coneflower. They were a pretty chill bunch and never bothered us, until I put my hand right over the exit hole while cutting back the coneflower. That's how I found out about their next, actually.

It's certainly possible that there is something else attracting them to that site. Some species of wasps will congregate on sweet deadfall fruit like plums and apples, and others are attracted to carrion.

The easiest way, I think, to tell if there's a wasp nest is to observe the wasps - you'll see a stream of them coming and going from the same area within the undergrowth. If you can run fast and perhaps have someone standing close by with a hose who could spray any oncoming angry wasps, you could poke around in the area with a very long stick or pole and see if you can stir them up. You have to be able to run really fast, though!