Leaf-cutter Bees belong to the Megachile family of bees and there are eight species in Britain. The three Leaf-cutter Bees that you might see in Bredfield are: Patchwork (Megachile centuncularis), Brown-footed (Megachile versicolor) and Willughby’s (Megachile willughbiella). Leaf-cutter bees do not have pollen sacs on their hind legs, as many other bees do. Rather, they collect pollen on hairs along the edge of the abdomen.
Brown-footed Leaf-cutter Bee Willughby’s Leaf-cutter Bee Patchwork Leaf-cutter Bee
Leaf-cutter Bees are solitary bees that nest in hollow stems, holes in trees and timber, or even in a purpose-built ‘bee hotel’. To protect her progeny from predation or parasites, the bee stuffs the hole with a layer of leaf after each egg is laid. The bee also leaves a stash of pollen as food for the larva when it emerges. The completed tunnel consists of a series of sections: food-egg-leaf; food-egg-leaf; and so on.
Fuschia leaves cut by a Patchwork Leaf-cutter Bee
The leaves are cut by the bee, precisely to size; then transported, in flight, to the hole. Garden Roses and Fuchsia are two favoured plants from which they will gather leaves.
Carrying away the cut leaf Depositing the cut leaf in the chosen hole
Leaf-cutter Bees are non-aggressive, though the females have a very mild sting which they might just administer if handled roughly. This happened to my son, who, on a summer’s day, was sitting on our wooden garden bench swinging his legs. We didn’t know at the time, but a Leaf-cutter Bee was nesting in one of the recessed screw holes under the bench, and he accidently brushed the bee whilst leg-swinging. He reported that the sting was “hardly anything”!
The nests of Leaf-cutter Bees are subject to parasitic raids by other bees (particularly Sharp-tailed Bees) and wasps (particularly Ectemnius Wasps). Whilst the bee is away leaf-cutting, those parasites will want to sneak-in and lay their eggs in the tunnel (see images below), where the parasitic larva can feed on the stored pollen and even on the Leaf-cutter Bee larva. Nest building is a hazardous activity for these bees and they have to be highly vigilant.
Ectemnius Wasp Sharp-tailed Bee
The Royal Horticultural Society has this to say about Leaf-Cutter Bees: “Leaf-cutting bees are fascinating pollinators and a valuable part of garden wildlife. The leaf sections taken during the collection of nest material does not usually affect the vigour of plants. They should not be ‘controlled’.”
To conclude, here’s a video of a Patchwork Leaf-cutter Bee at work:
All photographs and video taken in Bredfield by the author.