The barn board floor does score low on the janka scale, around 500.  Even though this is the case, the barn board floor is one of the very most durable floors you could ever install.  It really needs to be seen to be appreciated.  Due to it's inherently textured top with rough sawn marks, hair line cracks and other elements of character, the barn board is a great competitor in the longevity race and hides so much wear and tear.