According to The Hostapedia by Mark Zilis (2009), "...I've observed specimens in a few gardens and seen a number of photos labeled 'Kara' and can come to only one conclusion: 'Kara' and 'Tokudama Flavocircinalis' are the same plant. Differences in site, soil, and age would account for any perceived differences..."

Schmid (1991) cites Horinaka as the originator of the cultivar.