Nice lighting. Your subject seems a little soft. Did you do this on purpose? IMHO you need to seperate your subject from the background. If you move him away from the trees more and use a more open aperature you can blur out the background and put the emphasis on the gentleman.
TC
The focus on Burt seems a little soft to me. I think Burt is a very interesting character, and would love to have seen a close up of that face. Maybe in black and white. What a lovely portrait he would make close up. A face full of stories. Lighting seems ok, I may suggest to play with brightness/contrast a bit to maybe make it really punch. Burt looks like a great guy.
This would easily do better with a sharper focus. Burt makes a good subject though, you should try this shot again. Seems like it could do better with a smaller aperture (it might also help cut down on the blue tinges you get around the light areas at the top of the picture).