'Koto maru' is a dwarf selection from Japan that has a tighter compact habit. In the spring the new growth on 'Koto maru' is yellow-green with an orange-red border. Fall color on 'Koto maru' ranges from yellow to orange, finishing with a bright red. Being that 'Koto maru' is a witch's broom, 'Koto maru' often has a rounded center lobe on each leaf. 'Koto maru' is perhaps one of the smallest dwarf green witch's broom Japanese maples, reaching 2-3 ft in height and width in 10 years. 'Koto maru' is said to translate as "rounded harp".