My first insect

I now we have a lot of leafcutters in UT. They seem to prefer roses.

I did get stung by one in my garden once. At least I think it was a leaf cutter that stung me. I haven't seen them in a while, but I still see plenty of evidence of their existence. The ones I saw were a bit thinner looking and smaller, though. Hmmmm.....

Mine like to cut circles out of my serviceberry leaves, and this year for the first time, my native oxalis. Sometimes I can find their nests and watch them go in and out--mine dig burrows, often next to rocks or paving stones. Of course, now that I have a decent camera, I haven't found even one, though there were plenty of those tattle-tale leaf holes earlier.

Your memory is likely right. Megachilidae is a big family. According to Arnett's "American Insects" there are about 600 species in north america, ranging from small to big (7-18mm), and they have a lot of variety. I'm tempted to say that it's my favorite family, but really, any bug I'm looking into at the moment tends to become favorite!