Malus ioensis and M. coronaria are very similar and are distinguished from one another primarily by the persistence of dense wooly (tomentose) hairs on the undersides of mature leaves of Malus ioensis and their absence on mature plants of M. coronaria. Both Crabs are similar to Apple, but are more likely to have thorns and at least some shallowly lobed leaves. It shares these two characters with Crataegus (Hawthorn) which has shiny, smooth thorns as opposed to the dull thorns of the two Crabs which tend to have buds (or their scars) along the thorns. The flower petals of all three Malus species (Apple and Crabs) tend to be pink at least in bud and Hawthorn (Crataegus spp.) petals are white. Distinguishing these several similar species can be challenging. The two Crab species are far less common than Apple and several of the Crataegus species.

The natural range of Malus ioensis is mainly in Missouri, Iowa, Illinois and Wisconsin with isolated populations in Minnesota, Indiana and as far south as Texas and Louisiana. In Wisconsin it is mostly restricted to the southern third of the state, but is present in small numbers in several drier habitats in Brown County.