Plant stem stems are asparagus, bamboo shoots, cactus pads or nopalitos, kohlrabi, and water chestnut. The spice, cinnamon is bark from a tree trunk. Gum arabic is an important food additive obtained from the trunks of "Acacia senegal" trees. Chicle, the main ingredient in chewing gum, is obtained from trunks of the chicle tree. Medicines obtained from stems include quinine from the bark of cinchona trees, camphor distilled from wood of a tree in the same genus that provides cinnamon, and the muscle relaxant curare from the bark of tropical vines. Wood is used in thousands of ways, e.g. buildings, furniture, boats,
Cinchona people. Italian sources spelt Quina as Cina which was a source of confusion with "Smilax" from China. Haggis argued that Qina and Jesuit's bark actually referred to "Myroxylon peruiferum" or Peruvian balsam and that this was an item of importance in Spanish trade in the 1500s. Over time, the bark of the "Myroxylon" was adulterated with the similar looking bark of what we now know as "Cinchona". Gradually the adulterant became the main product that was the key therapeutic ingredient used in malarial therapy. The bark was included as "Cortex Peruanus" in the London Pharmacopoeia in 1677. The "fever tree"