Etymology and distribution of 入塩.

Irishio 【入塩】^{レベル2
About 20}  The Japanese surnames etymology dictionary.

Iwate-ken Toono-shi . A variant of 臼舘 . Iwate - ken Toono - shi In Aosasamachi - Sasa, tell the fact that officials mistyped Usurator 's surname after the office became a fire in the Tokyo era. 臼舘 Usudate reference.