lady's thumb

Common Names: 
smartweed, lady's thumb
Scientific Name: 
Polygonum
Polygonum leaf, closeup
Submitted by DanFauxsmith on Wednesday, September 17, 2014 - 19:35.
Notes: 

I'm not completely sure this is lady's thumb, but the dark marking on the leaves fits.

Flower Color: 
pink
Leaf Shape: 
Lanceolate
Location Name: 
Construction site near Alewife Reservation Cambridge, MA
United States