I was reviewing the planter pots on Amazon when I came across this in one of the reviews: "A Trade gallon is a term used to denote the sizes of standard plant containers in horticultural industries. A trade gallon is equal to approximately .71 U.S. liquid gallons." I DIDN'T KNOW THAT. Since it is seldom that the pots one sees in garden sections are labeled with their gallon capacities, I've always determined their number of cubic inches and then converted this into dry gallons, using 268.89 cubic inches per gallon as the key. I have to wonder how widespread the practice is. I know a 2X4 isn't really 2" X4", but does this sort of deceptive practice exist in every industry? Is there anything that can be believed? More importantly, I'd just like to know if this labeling practice is universal throughout the nursery industry.