Momiji is a Japanese word that means autumn leaves or maple. It is also the name of a type of Japanese maple tree (Acer palmatum) that is often used as a bonsai material. Momiji bonsai are prized for their beautiful foliage that changes color in the fall, from green to yellow, orange, red, or purple. Momiji bonsai are also known as yamamomiji, which means mountain maple, because they are native to the mountainous regions of Japan. Momiji bonsai require partial shade, good drainage, and regular pruning to maintain their shape and health.