On my way home tonight I decided to stop down by the Shenandoah River to see what I could see. The water was very high and passage along the bank was impossible. So I decided to walk back down the road to check out the Dutchman's Breeches I spotted as I drove in. Last week or so I wrote about finding some that had just started to come up. Well, now they are in full bloom and mixed in with the Bloodroot. When I was doing research about Dutchman's Breeches I read that they are pollinated by long tongue bees but occasionally other bees will cut holes in the sides and rob the flower of its nectar bypassing the pollen. So I decided to see if I could find evidence of that happening to this stand of flowers. Sure enough almost everyone had slits in then.
I read in my hot-off-the-press "Tracks and Signs of Insects and Other Invertebrates" by Charley Eiseman and Noah Charney that large carpenter bees, Xylocopa species, use their proboboscis to cut narrow slits in the flowers to gain access.
The photo in the guide show the tips bitten off by nectar-robbing bumblebees (Bombus) but the ones I was seeing were more like slits so I have concluded they were made by the Xylocopa species.
See more interesting things at Outdoor Wednesdays.