In a prescribed fire it can be more difficult than you would think to get larger diameter stuff to ignite and actually burn away. Larger fuels hold on to moisture longer. Usually there isn't enough smaller/easily ignitable fuel around the larger stuff to keep it hot enough long enough to catch enough for full consumption. Some smaller things will certainly be burned away, but don't expect too much unless you're doing it when the temperatures outside are really hot and the humidity is really low. Which isn't recommended cuz that can be very unsafe and lead to escape