Meet the Air Potato, an Invasive Vine (Part I)
January 29, 2013
The air potato, Dioscorea bulbifera) is an invasive species.
How Invasive is it?
It is so invasive … that some communities stage annual round-ups where they collect tons of the tubers (bulbils).
It is so invasive … that it has been listed as one of Florida’s most invasive plant species since 1993 and, in 1999, the Florida Department of Agriculture and Consumer Services placed it on the Florida Noxious Weed List.
It is, in short, among the most aggressive weeds ever introduced into Florida. It was brought to the Americas from Africa during the slave trade and introduced into Florida in 1905. It has spread throughout the state.
The air potato is a twining vine. It grows fast – up to eight inches per day. It can grow 70 feet or more in length. Do the math: it can get that long in less than two weeks! It typically climbs to the tops of trees and utility poles and can overtake native plants.
It gets its name from the aerial tubers (bulbils) which are roundish in shape and actually look like a potato. (Don’t make the mistake of trying to eat them. They are poisonous.) These tubers are the primary way the plants spread. Even tiny bulbils can sprout and form new plants. Bulbils can move in contaminated brush, debris or soil. Mowers and other brush-cutting equipment, birds and other animals may also help spread them. They can also spread via water bodies and floods.
This is one persistent plant — hard to control or get rid of. Chemical control can be effective, but multiple applications are usually required because above-ground bulbils or underground tubers can re-sprout. Many communities in Florida, including Hernando, Alachua and Duval counties, stage air potato roundups. (Gainesville just completed one last weekend.) Volunteers typically collect the tubers, which are then carefully disposed of.
Current air potato management practices are costly, time consuming, temporary, and have negative effects on surrounding vegetation and organisms. Fortunately, there is now a natural alternative to this sweat and toil in the form of a natural enemy, a leaf-eating beetle, Lilioceris cheni, whose sole purpose in life is to find and eat D. bulbifera.
State and federal scientists are rearing and releasing the beetle throughout the state. More about that shortly.