Ginkgo biloba 'Mighty Munchkin' comes from the U.S.A. is one of three selections made by Gary Handy from variants of  'Chris's Dwarf' (which has shown some instability in cultivation). The other two are Munchkin' and 'Munchkinot'. 
 
Description - Ginkgo biloba 'Mighty Munchkin' was selected from a variant of Chris's Dwarf' that had the little tiny leaves, typical of Chris's Dwarf' but exhibited a strong leader with little or no branching. The eventual height and width are not yet known, but one such example is purported to be more than 3 m with a few tiny branches. Mr. Handy informs us that 'Mighty Munchkin' also pops up in batches of 'Munchkin', which is probably not surprising given is parentage.