Oat herb consists of the green aerial parts of Avena sativa harvested before the grain fully matures. Western herbal traditions have described it as a restorative or nutritive preparation during periods of fatigue, nervous strain, and convalescence. The European Medicines Agency recognizes traditional-use preparations for mild mental stress and as an aid to sleep, based on longstanding use rather than strong clinical evidence.

Oatstraw's symbolism grows from oats as a sustaining crop and from the flexible stems that bend without easily breaking. Contemporary practitioners associate it with nourishment, calm, patience, stability, and recovery after strain. Correctly identified dried oatstraw may be kept in a sealed calming sachet or dream pillow, added to a strained external ritual bath, or placed as a symbolic offering of gratitude and provision.