What is this lawn weed. It is all over my Upper Arlington street? What is...
Although your picture is very clear it is hard to identify the plant without more information. I believe your plant is Asiatic Dayflower.
Asiatic dayflower (Commelina communis) can be a problematic weed in lawns and gardens. Another name for this plant is wandering jew. It is erect, unbranched, grasslike, glabrous, becoming prostrate and profusely branched.
The PDF version of Purdue's Fact Sheet can be found at www.btny.purdue.edu/weedscience which has information as to effective herbicides on Asiatic dayflower.