I've Got Leafcutters!

[The15thMember]

Some of you may remember that I got a native bee observation hive for Christmas.  I painted it and hung it up on my mom's washline in late March.  I did see one mason bee checking it out in early April, but no activity after that.  I started to get concerned that it wasn't going to work, because some earwigs moved into the top tube, and mold and some sort of wood fungus started growing in the bottom tube.  Then last week my sister came in the house and said that the bottom tube was capped with leaves!  I went out later and took a look and, sure enough, the bottom tube was indeed capped and there was another nest started in the tube above it.  Here's some pictures.  I love this observation hive, it's so cool!  We've been seeing the bees' little hole-punch-like circles out of leaves in the forest too.  I'm not sure why the bees didn't fill the tubes up all the way.  Maybe they were just too long for their liking. 
   
     

[van from Arkansas]

That is totally to cool.  Are the leaf cutters metallic colored?  My knowledge of Mason bees is scant.
Cheers

[The15thMember]

That is totally to cool.  Are the leaf cutters metallic colored?  My knowledge of Mason bees is scant.
Cheers

I believe they can be metallic, but there are many many different species of leafcutters. I unfortunately have not seen the actual bees, so I can?t say what species these are. I also had some leafcutters nesting in a paper straw bee house I made last year that were much smaller than these. They were striped sort of like a honey bee and were not metallic.

[The15thMember]

I finally saw one of the female bees in the nest today. I believe they are alfalfa leafcutters, which are a European species brought to the US for pollination that has now become widespread. They are good pollinators of alfalfa (obviously), carrots, canola, and legumes.