Oatstraw comes from the green stem and leaf of the oat plant, harvested before the grain matures. People use it as a nervine herb. Many take it as a tea or tincture, often in the evening, to ease mild stress and encourage restful sleep.
Unlike oat groats or bran, oatstraw provides very little fiber. Evidence for its traditional uses remains limited. Most of what we know about its effects on the nervous system comes from long standing practice, not clinical trials.