Air Potato
Dioscorea bulbifera
Family: Dioscoreaceae
Natural History
Air potato (also called potato-yam, air-yam, Chinese-potato or devil's-potato) is a member of the family Dioscoreaceae (yams). They were introduced from Africa in the early 1900's as an edible landscape plant. The tubers may be cultivated as a starchy food source, but are generally bitter when grown wild.
The vines are extremely aggressive and grow into dense masses that quickly out-compete native vegetation. They often climb high into the canopy and over-top even the tallest trees. The prolific aerial tubers help the plant to spread quickly. Even though the vines and aerial tubers are deciduous and lie dormant for the winter months, the underground tubers may still sprout and continue the spread of the plants year-round. These vines are often seen climbing into the foliage along forest edges or even in urban settings. They pose a serious threat to forested habitats.
Chemical compounds are extracted from the plants to produce steroids and birth control pills. West African tribes grow air-yams as an important food plant. The tubers, which are said to have a potato-like flavor, are boiled twice before eating, to remove any toxins and bitterness.
Air potato is similar to the native species, wild yam (Dioscorea floridana), which has shorter leaf blades and no aerial tubers. It also resembles winged yam (Dioscorea alata), which has opposite leaves and winged stems.
Air potato is currently found in 23 counties in Florida and is still spreading. Many cities, including Gainesville, have held wintertime "air potato roundups" to collect and destroy any tubers found on the ground in natural areas, but the events have had little impact on the tubers that are already underground. Recently, however, a leaf-feeding beetle, Lilioceris cheni, was introduced into Florida from China for biological control of air potato. Extensive testing has shown that the beetle only consumes the leaves of air potato and will not damage any other plants. By devouring the green leaves on the Air potato vines, the beetle prevents photosynthesis and forces the plant to exhaust its underground energy reserves. Early results from the release are very positive and suggest that the beetles may succeed in controlling or even eliminating this weed.