Organic leafy stems are used. May be called Vervain, there is a true Vervain, however, Vervain officinalis. This oil is a fever reducer and sedative when simply inhaled. Is effective during an asthma attack. It can be used as an anti-inflammatory as well. Good for nervous indigestion, hangovers, and to refresh and uplift. This oil is phototoxic and is best not applied to the skin. Be aware that Lemon verbena is costly and is often adulterated.