'Door-pine'. Pine-branch and bamboo decorations are hung on the front of shops and houses at New Year, together with the February-flowering plum (ume). The evergreen pine represents continuity, the sharply cut bamboo straightness and sincerity, and the ume new life. The custom is now universal in Japan although those living near the Ikuta-jinja in Kobe reportedly do not decorate their homes in this way, ever since the kami of the shrine indicated his dislike for pine trees by sending a flood that washed away all those around his shrine—in the eighth century.
See also Kazari.
A Popular Dictionary of Shinto. Brian Bocking.