[masklinn]

> A once in a hundred year weather event would be enough to keep a population going.

The article notes that it was nowhere near enough, and with the loss of its primary dispersers the once-widespread genus had enormously shrunk in variety and range both before it got recycled as natural fencing:

> According to my field guide, Osage-orange has a limited natural range in the Red River region of east-central Texas, southeastern Oklahoma, and adjacent Arkansas.

> [...]

> fossils tell us that Osage-orange was much more widespread and diverse before the megafaunal extinctions. Back then, Osage-oranges could be found north up to Ontario, and there were seven, not just one, species in the Osage-orange genus, Maclura.

(sp: there are 12 extant species of Maclura according to the wiki — most of them from asia though one is native to south america and one central america, I expect the author implied "in NA")