Original sentence: Generally speaking, a distance of 50 miles (83km) from cut site to final burning site is considered the longest distance that firewood should be moved.Good forestry practices and improvements in devices that use firewood can improve the the local wood supplies
Edited sentence: Generally speaking, a distance of 50 miles (83 km) from cut site to final burning site is considered the longest distance that firewood should be moved.Good forestry practices and improvements in devices that use firewood can improve the local wood supplies