I thought I was heading to a guided walk at Hopkinton's Blue Pond to be led by Doug McGrady, an absolutely incredible botanist, but when I arrived at the parking lot at 12:45, there was no one there. Turns out I had the wrong day on the calendar for the Rhode Island Wild Plant Society-sponsored exploration, but, since I was already there, I went anyway to trek the increased edges of the one-time pond that was now a shadow of its former self, eight years after the dam that created it burst during the epic spring flood of 2010. A good deal of lower Blue is now a wet meadow, and it's a botanical wonderland of unusual plants. It's also a splendid habitat for unusual dragonflies, and as I watched the swaying grasses, sedges, and perennial flower-tops, I noticed a lot of sparkling wings. These in the photo belong to a large odonate known as the Carolina Saddlebags, on account of the red-brown hind wing patches that observers likened to the satchels thrown on the backs of horses and other pack animals. That was more apt than the namers figured: Tramea carolina is a migratory dragonfly, although, as near as scientists can determine, it doesn't carry external baggage for its trip south.