Pretty much all we have around here is corn and he was no where near a field. He was over MY house. I thought he was going for a loop when I first saw him. He didn't quite get vertical then kicked the rudder over just before stalling. Like a really sloppy hammerhead. Then as soon as he picked up airspeed coming down, he went right back up and did it again. This happened at least 3 times in a row.
As far as juding what type of aircraft it was. I'm sorry for not being able to identify every biplane ever made. It was definitly not a modern design though.
As far as how high it was, I'm horrible at guestimating altitude, but this guy was low. I found someone else at work who had seen the event and she said he was flying lower than she had ever seen someone fly before. I've seen a lot of full scale and model shows as well as flying models myself for 10 years and I know if something had gone wrong, this guy was not going to be able to pull out.