The tires are: Carlisle Versa Turf 18x8.50R10 4 ply, and are made in China. There are a whole bunch of other various numbers around the sidewall, but aside from what I take to be an equivalent metric size, nothing else I recognize. There is not speed nor capacity value.
The sidewalls are bulged in various places, and the fibers of the plies are nearly visible. There are cracks in the sidewall through which plies can be seen. One of those burst, hence the flat, which made this all apparent. The tires were always inflated to the specified 22PSI, and the loader has been on most of the 240 hours total time on the tractor since new.
By comparison, similar diameter 6 ply airplane tires have lasted me 15 years, as did the front tires on my previous JD650. These tires are pitiful compared to those! Thus, I won't be spending $340 each to replace them!!!
They are a less common size, as the 10' rims rims (which would more commonly be 8") are that size to fit over the front four wheel drive lower gearboxes.
I'm just disappointed in John Deere, why cheap out on tires!