Ranunculus (Buttercup)

Last night I noticed a lot of these leaves growing under the edge of our deck, a new candidate for the photo scanner. The leaves looked somewhat familiar, but I didn't recall where I had seen them. I started looking at some weed lists on the web, but didn't get far. Then today we went for a redux of yesterday's Guppy Falls wildflower walk. Karen couldn't attend yesterday's walk lead by an actual qualified guide, so I made a poor attempt to show her what she missed. I snapped a bunch of pretty-much random shots with the Cyber-shot, and one that I got looked to me like buttercups when I brought it up on the computer tonight. I did some googling to see if these were native buttercups and found that they were probably not. In fact they look like the fairly invasive common weed called creeping buttercup (Ranunculus repens), and I'm pretty sure these match the leaves that I noticed under the deck last night. This makes sense because part of our nearby side yard is nothing but mowed buttercups.

Update, Jun. 3, 2011: After looking at a lot of buttercups in our yard, I think I was pretty much out-to-lunch in equating the leaf under our deck with the flowers at Guppy Falls. More investigation is warranted.

Update, Jun. 3, 2011: My latest SWAG is that the bottom picture looks more like a Geum, maybe a yellow avens (Geum aleppicum).