Im not sure if its the head of the tail but it starts near the lowest green leaf in the bottom center of the image.
This snake wouldnt bite anyone though... his outstretched positioning tells me he was on the move when the image was taken. However, snakes and their camoflage are the main reason why when I walk through wooded areas like this I carry a stick to tap the ground with as well as walk heavily. Heavy walking will more often than not give the snakes plenty of warning to get out of your way.