flies

I've just been in the garden and found a tree with loads of big flies on it. I suppose there must be a nest somewhere. How do I find it, and kill all the flies?

 

Oh, we saw this in Austria last year, it was the same time of the year too, perhaps just a wee bit earlier. We had never see such before.

 

Hi linlin. Flies don't live in nests. What tree was it? I've noticed that flies seem to like Laurel for some obscure reason. All the best