Garden friend or foe?

Seeing that the new leaves on one of my roses had large holes cut from the edge, my first thought was “It’s the dreaded vine weevil!!” The adults eat the edges of leaves while the eggs that they lay in the soil go on to develop into white C shaped grubs that eat the roots of the plant and eventually kill it. I’ve given up growing heucheras because they always succumb to vine weevil, and it can spread to a wide variety of other plants. Definitely a garden pest.

I rushed to Google, and what I found was reassuring. While vine weevil nibblings are much more rough and uneven whereas these are very neat, consistent and circular. Vine weevils tend to come into the garden in new potted plants but not only has this rose been established for years, no potted plants have been introduced nearby. Google tells me it is much more likely to be the leafcutter bee.

Leafcutter bees are bees that use leaf sections to make nests. They take round sections from leaves thus creating these interesting patterns. Their Latin name is Megachile and there are seven species in the UK. They are widespread and their food is nectar and pollen. The wingspan is 8-14mm and they are dark brown bees covered in lighter brown or orange hairs.

The bees are solitary. The female bee uses her jaws to cut a section of leaf from the foliage of the plant, often roses, and then flies back to the nest site with the piece of leaf slung between her legs. The females use leaf pieces to construct cells within their nests. They are active from late spring to late summer. The nest site may be a naturally occurring tunnel, such as a plant stem, or it may make a tunnel for itself in rotten wood or dryish soil. Inside the nest, the leaf pieces are manipulated to form a thimble-like structure which is then provisioned with a mixture of nectar and pollen. When sufficient food has been gathered, the female bee lays a single egg on the stored food and proceeds to cap the cell with circular pieces of leaf. This process is repeated until the nest contains about 20 larval cells.

The leafcutter bees are necessary pollinators and are a valuable part of garden wildlife, so are to be encouraged. The section cut from the leaves taken during the collection of nest material does not usually affect the vigour of the plants.

Once I realised that the circles aren’t the work of the dreaded vine weevil, they began to look rather attractive to me. The bees also use bee hotels. So perhaps it is a resident of my newly installed Bee Hotel? That is a result!

I can definitely say that the leafcutter bee is a garden friend.