Tis okay but difficult to get exact. More difficult is to look at a pile of wood on the ground and then estimate how much is in it. For sure it is difficult to get the cubic feet amount but it can be done with a little time and math. However, I find that most people just do not like to work with math so keep it as simple as possible is usually the best. But, how to keep it simple? That is the question.
Pi r*2 h/3. For math geeks thats assuming that pile is a cone. For me a loosely thrown pile is more of a rectangular base. To make a cord I add 30% volume of a stacked cord to equal a loosely loosely thrown cord so 128/3 +128= 191 sq ft. I always err to the customers favor.