Diligent insects in the summer garden

Allendale, Northumberland There’s a low hum from bumblebees foraging deep inside the comfrey flowersThe day presses down, close and sultry, as I sit cross-legged in front of our three compost bins. There’s a low hum from bumblebees foraging deep inside the nearby comfrey flowers, but I’m interested in a different type of bee. In front of the wooden bins are some large stone slabs, the thumb-width gaps between them unmortared. There, coming and going, are several large black bee