falling paulownia leaf; sign of autumn
A single paulownia leaf falling is a traditional poetic image that signals the beginning of autumn. Often used in classical literature and haiku.
A single paulownia leaf falls, and one knows the autumn of the world.
Seeing a paulownia leaf flutter down in the garden, I felt the arrival of autumn.
From 桐 (paulownia) + 一葉 (one leaf). The phrase is associated with the classical Chinese proverb '一葉落ちて天下の秋を知る' (A single leaf falls, and one knows the world's autumn), where the paulownia leaf is a traditional symbol of autumn's arrival.