Hazards: sliping on the wet grass and the mud, tripping over fence ect as well as the winter weather but mainly human error. this is a good place as it lead the audience into the darkness with the protaganist and sets up the story for the audience.
All of the above hazards along with the possiblity of falling into the stream that runs beside the path and catching youre self on the barbed wire.
With this scene there is alot that could go wrong as it is a open are we could slip and trip as before, whilst trying to hit our actor we may hit him for real and we may use the tree for a camera shot and we may slip and/or fall.
This is a good loacation ton film because we have a vast array of potential shots like a shot from a tree or from the bushes.