Well… to a certain extent. Here in the u.S., where we still have substantial sized herds of Federally protected wild horses (in one case, the horses are closely related to the original Spanish Barbs, imported by the Conquistadores). Almost all of such herds exist in the arid semi-deserts of the west. Few, if any are in the wetter areas, so woof and tambourines answers are semi-correct.
We have working horses here in the western U.S. and have become fairly adept farriers. However discussing this very question with a veterinarian revealed the more important existence of a bacteria that always attacks the 'horn' part of the hoof from the underside… the foot side of the hoof.
It enters the 'white line' boundary of the inner hoof from the outer, tough horn. (Seen when the 'frog' of the under foot is cleaned before shooing). The bacteria is acquired from the soil in any damp area, such as drinking water sources, etc. The bacteria attacks only the horn, making it very susceptible to splitting and breaking. This can even be seen under certain circumstances in shod, domestic horses...