At first, whole rice straw was cut with scissors as whole particle. Rice straw could be divided into fractions by morphological character; stem, leaf and panicle. Hoshikawa (1989) described that the stem of graminaceous plants is also called the culm. The culm consists of successive nodes and internodes. The leaf consists of the leaf sheath and leaf blade, and at the junction of them are a pair of auricles and the ligule. Externally, the swollen basal part of the leaf sheath is attached to the node. The leaf sheath itself encloses the stem internodes above this node. The panicle, also called the ear, is