I simply love the colors and the beautiful bokeh of this photo. Late autumn is the best time for this type of photography. Using a prime lens with F2.8 would helps a lot on getting nice bokeh. Generally a 90mm – 105mm prime lens with F2.8 fits perfectly for this purpose. Please remember that most of the forests tend to be little dark in late autumn period. A sturdy tripod would help a lot on low light conditions rather than high ISO values. Your picture would look noise-free and beautiful.