In the wake of publication of a haiku collection "Koki" (Yellow Flag) in 1935, he fell away from 'Hototogisu' and took part in 'Ashibi' as Dojin, and he became a leader of Shinko Haiku Undo with Shuoshi MIZUHARA.
1935年に刊行した句集『黄旗』を契機に、「ホトトギス」を離れ「馬酔木（あしび）」に同人として参加、水原秋桜子とともに新興俳句運動の中心的存在となる。