The road was fenced so I pulled up to a house and asked for advice - while a bit hesitant Rob ended up allowing me to camp on his land. Nice guy who told me about the "double g's" looking like goat shit with 5-10 mm long thorns sticking out and breaking off in the tire. After fixing all the flat tubes, we spent an hour looking for thorns but couldn't get them out so instead I put gorilla tape on the inside of the tire. I also got a nice shower so the day ended well...