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Chinese Sweetgum

Photo: A Chinese sweetgum
Chinese Sweetgum

Though the spiky, fallen fruit balls of the sweetgum are hazardous to barefoot walkers, they intrigue chemists and doctors. The seed capsules contain shikimic acid, a key ingredient in the drug Tamiflu, used to fight avian bird flu. The wide-ranging American sweetgum, L. styraciflua, contains significant amounts of this antiviral agent. To understand the sweet gum "family tree," National Geographic sponsored Stefanie Ickert-Bond on a study and collection mission to seldom visited areas of south China. She reported that the trees managed to migrate across both the Bering and the North Atlantic land bridges. (Liquidambar formosa)
Photograph by Steffi Ickert-Bond

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