So, why is there only the pine tree drawing? Well, the pine tree is an evergreen that does not wither during the year and lives a long time. In Japan, it has been thought of as a sacred tree since ancient times. Even today, there is a custom of decorating the entrance to homes with pine branches at New Year’s. The pine drawn at the back of the Noh stage is an old tree (oimatsu). Since deities are believed to reside in this tree, the picture is an expression of the stage’s role as a place of exchange between the deities and humans through dance. However, because the actors face the audience when they perform, they have to direct their buttocks toward the deities in the pine tree, which is highly irreverent. Therefore, a real pine tree is placed behind the audience seats, and the pine drawing on the stage is said to be a mirror image of it. That is why the whole back panel on which the old pine tree is drawn is called the kagami ita (mirror board).
While that is a rather expedient interpretation, it can certainly be said that the stage expresses a wondrous space where fact and fiction are already intermixed and where the drama mingles the real world and the illusionary world. In the plots of the majority of Noh plays performed here, characters from this world (the real world) and that world (the spiritual world) have an encounter beyond time, reveal their thoughts, clash with each other, and eventually the spirit departs.
Throughout the play, the background does not change, only a few props are brought onto the stage, and the main actor’s face is covered by a mask, so his expression never changes either. His gestures also are only gentle movements in tune with the music. It is, in other words, a symbolic play. Members of the audience must picture the setting in their own minds and imagine the mental state of the performing characters.