I went over and talked to the man. He is Larry Mattlage, who says he is on his property and just posted a no-parking sign.
"We're going to start doing our war and it's going to be underneath the law," he told me. "Whatever it takes. So y'all go find another place to do whatever you do. 'Cause this is our front yard and back yard."
I asked, "Do you mean the protestors?"
Wait... Now there's some Secret Service and cops. I'm going to get closer to hear what they're saying. People in bullet-proof vests are here now. Two Secret Service agents are now walking up his driveway towards his house, with Mr. Mattlage. A member of the Sheriff's Department has arrived. Mr. Mattlage is waving his arms now. All of them are now walking back this way.
An audio clip of the conversation with Larry Mattlage, can be found here