This study sounds way off. It was by NASA which means they were trying to tell a lawn from satellite. That's probably tough--having to discount natural grass land and farms (which there is a fair amount of) and accurately getting the percentage. Not to mention seeing through tree cover to see if there is grass below. There is a lot of green out there, not a whole lot of it is mowed lawns.<p>50,000 square miles is 1/70th of all land in the US <i>including</i> Alaska (3.5m sq mi total). If you've ever driven through the country, 1/70th is not a mowed lawn. You can drive for hundreds of miles without seeing a single one. If you discount Alaska the total is 1/58th.<p>Looking another way that would be 32,000,000 acres of lawn. which comes out to 1/10 acre of lawn per person in the country. At first that seems more reasonable, 1/10th of an acre isn't a lot, but that's per person not household. A 4-person family comes to 4/10 of an acre--a decent sized lot. And since there are large numbers of people with no lawn the number increases for people who actually do (10m in NYC without one means 10m other people would need twice as much space, etc).