These unpleasant insects seem to be everywhere this year, and it's been a full-time-job keeping up with them. Mostly they make their earthen nests in walls or behind pictures, but occasionally they build them (as they did last year) amongst Lady Magnon's clothes. She was not happy.
Normally we have just one or two that come into the house, and one can hear their high pitched buzzing quite easily. But this year they are of plague proportions.
They often build several of these inch-long earth 'nests' side-by-side, which they fill with several paralysed spiders before the eggs are laid. The newly hatched digger wasps then have their own food supply, locked into their new home, which nourishes them prior to digging themselves out.
I thoroughly approve of anything that consumes spiders, but it's the wretched earthen nests all over the place that I really don't like. Any solution to our problem would be gratefully accepted.