The sakaki is the evergreen tree whose branches are the standard offering and ritual plant of Shinto, an unassuming broadleaf evergreen held sacred as the proper offering to the kami.
The branch that is offered
Branches of sakaki are the ordinary vegetal offering in Shinto worship: decked with paper streamers and strips of cloth they become the tamagushi, the offering branch that priest and worshipper present to the kami with a bow, and sprigs of the evergreen stand in vases on the household shrine and are used to adorn the sacred space. The plant is thus woven through the ritual of the tradition, from the great shrine to the home, as the standard green offering, and its use in this way is one of the constants of Shinto practice.
Why the evergreen
The choice of an evergreen carries meaning: its unfading green through the year suits it to the marking of the sacred and the enduring, and evergreens have widely been associated with the presence of the divine and with life that does not die. The sakaki grows in the warm-temperate forests of Japan, and where the true plant does not grow other evergreens are substituted, but the association of the sacred offering with the living evergreen branch is constant. That so ordinary a plant should be the fixed ritual offering is characteristic of Shinto, in which the natural world, a tree, a rock, a waterfall, a mountain, is the ordinary bearer and object of the sacred, and the humble sakaki branch is the everyday instance of it.