I think this is wild strawberry. As I started to pull it, this ditty from my Boy Scout days began to play in my head "Leaves of three let is be." I used Google to search and ended up here! I live in Centreville, VA, about 35 miles WSW of Washington, DC. This is comming from the neighbors grass under the bottom rail of a split rail fence. I took the pictures and you have permission to use them. The first shows the leaves and possibly the dried up flower. The second shows the vine. The vine grows into the ground when the flowers touch.

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