A longitudinal section of a stem of the greater celandine, Chelidonium majus, a member of the poppy family. The lower third of the picture is the base of the stem at ground level. The stem is covered with surface hairs. The cut surfaces show patches of an orange latex bleeding from specialised vascular cells called laticifers, that have been sliced open. Latex is a watery emulsion of many chemicals, including alkaloids, gums and enzymes. It quickly thickens and solidifies when exposed to air, and in nature can act as a sealant for damaged tissue. Many plant families produce latex; the most important is rubber.C. majus is used in herbal medicines as an infusion made from the dried plant. Traditionally the fresh latex was applied topically to warts; the latex can cause liver damage if ingested. The plant is a weed of disturbed ground in Asia, Europe and the USA.