Posted: Wednesday 12 September 2012
by Richard Jones
We have leaf-cutter bees nesting in the wind chimes. These, however, being bamboo, never so much chimed as clonked.
We have leaf-cutter bees nesting in the wind chimes. These, however, being bamboo, never so much chimed as clonked. Now they have lost all tone and tune as they become slowly bunged up with drying vegetable matter.
As ever, it was the bobbing flight of a piece of bright emerald leaf that alerted me to the bee’s presence as it floated past the kitchen window. Every year I see the distinctive semi-circular cuts removed from the rose leaves, but it’s ever a treat to see your actual bee at work. The scissoring of the leaf itself takes only 15-30 seconds, then the bee must take its cargo back to the burrow. She does this by folding the leaf over and carrying it, curved under her body, as she supports the front of the segment in her jaws. On the free outward journey from the nest the bee’s flight is straight and strong, a bee-line presumably, but on the return, heavily laden, she weaves and zigzags.
According to the literature, it takes six to 14 leaf pieces to make the sides of a single cell, and another six or seven for the lid. A tunnel nest contains six to 10 separate cells, each carefully constructed, then filled with a cake (or ‘loaf’) of nectar and pollen before a single egg is laid in it. Then it is closed and the next thimble-sized cell is added hard up until the tunnel is full.
Unlike bumblebees and honeybees, which collect pollen using special ‘baskets’ of long stout hairs on their back legs, leaf-cutters wallow in the stuff, and bring back a matted mess of pollen on the thick brush of golden or silvery hairs that covers the underside of the abdomen.
The colour of these pollen-collecting hairs is important in trying to identify leaf-cutters, there are seven species in the UK, and it is one of the six golden-haired species I have in the bamboo. It’s unlikely to be the coastal Megachile maritima or heathland M. circumcincta, and I don’t think they are the very large M. ligniseca. That still leaves three relatively common garden species: M. centuncularis, M. versicolor and M. willughbiella. Despite their relatively large size, getting nearer to a scientific name for my leafcutters is virtually impossible without microscopically examining the jaw teeth, the shaggy (or otherwise) hairs on the foot joints or the shape of the tail-tip. Although I’m quite impressed with the pictures I managed to take, the camera in my phone just is not up to the optical quality needed to see these key features.
30/09/2012 at 20:19
Saw my first leaf-cutter only a couple of weeks ago Richard. Didn't get a chance to look at its underside...
30/09/2012 at 22:58
Saw one this year making a home underneath some sempervivums in a pot next to a sheltered wall. It was fascinating to watch this little creature tunnelling under the gravel into the gritty soil. It looked as if it was flying in on a little green magic carpet. Kept me entertained for hours!
01/10/2012 at 06:35
I love watching Leaf Cutter bees I always have one nesting in my greenhouse behind the wood with the plug on it and I have noticed some bees have been using my small bug box
I tried to take a photo of a leafcutter bee - if you look closely you may be able to see it
Pam LL x
05/10/2012 at 01:05
This year I have had a big problem with leaf cutter bees. They have ruined roses, Dahlias, pear, plum and the gooseberries my plants are bald totally bare of leaves. Any ideas on persuading them to move some where else. I didn't mind them last year when only a few leaves were nipped and it was fun watching them cart the leaves to the nests but this year they have taken over