Poppy straw (also known as opium straw, mowed opium straw, crushed poppy capsule, poppy chaff, or poppy husk) is derived from opium poppies (Papaver somniferum) that are harvested when fully mature and dried by mechanical means, minus the ripe poppy seeds. Opium poppy straw today can be one of several different things. It is what remains after the poppy seed harvest, that is, the dried stalks, stem and leaves of poppies grown for their seeds. The dried leaves and stalks are harvested after the seed pods have been used for traditional opium extraction. The field dried leaves, stalk and seed pod are used in commercial manufacture of morphine or other poppy alkaloid derived drugs, by first processing the material to make poppy straw separating the seeds then making concentrate of poppy straw, where no extraction using traditional methods of latex extraction has been made. The straw was originally considered an agricultural by-product of the mechanised poppy seed harvest, which was primarily grown for its edible and oil-producing seed. This changed in 1927 when János Kabay developed a chemical process to extract morphine from the crushed capsule. Concentrated poppy straw consisting mainly of the crushed capsule without the seeds soon became a valuable source of morphine. Today, concentrate of poppy straw is a major source of many opiates and other alkaloids. It is the source of 90% of the world supply of legal morphine (for medical and scientific use) and in some countries it also is a source of illegal morphine, which could be processed into illegal heroin. The 1961 Single Convention on Narcotic Drugs defines poppy straw as "all parts (except the seeds) of the opium poppy, after mowing". Decorative Dried Flower producer/growers and wholesalers, hand pick the decorative mature seeded pods/heads with or without the stalks for use as floral decorations for visual gratification in arrangements. These are then mechanically dried at high temperatures in large kilns to render insects dead and the seeds unviable so that the harvest consists almost entirely of the dried flowered seeded pods/heads (for ease of transport, artificial stems are added afterwards, e.g. bird seed wreath making, floral arrangements and wedding boutonnières or arts/craft projects). The seeds used for this market are especially chosen for the size and shape of the mature poppy seed pod/head and not alkaloid content. Many varieties, strains, and cultivars of Papaver somniferum are in existence, and the alkaloid content