Etymology and distribution of 椿屋.

Tsubakiya 【椿屋】^{レベル2
About 10}  The Japanese surnames etymology dictionary.

Toukyou-to . Estimated from the shrine's fish (leek) and island-like land. There is a belief that Negi surname was related to Ise Shrine of Mie-ken Ise-shi . Period, location unknown. 根木 Negi reference.