New plants are introduced into our local communities regularly. We generally don’t pay much attention to the ones that are considered weeds, and cultivate the ones that produce or provide a natural enrichment to our environment. There has been local attention to a non-native invasive plant here in Florida called an air potato. This plant/weed is very different in that it grows yes, literally like a weed, in fact, it can grow 8 inches a day and produce large numbers of potatoe like growths that sprout new plants. The growths are bulbils and are considered a species of yam, they are toxic and should not be consumed. The bulbils make the plant robust and fast growing, for it is the bulbils themselves that serves as a means of dispersal. The aerial stems of this plant die back in winter, but resprouting occurs from bulbils and underground tubers. The short winters in Florida helps to make this plant thrive even better.
The main reason the air potato plant or vines is a threat is because it typically climbs to the tops of trees and can take over native plants. The plant is quite versatile and invades a variety of habitats, including pinelands and natural area hammocks. It quickly can engulf native vegetation in natural areas by climbing high into tree canopies. The struggle to remove these hardy pesty plants involves several methods, some surprisingly not bad for the environment at all.
Chemical control is still one of the most effective means of control, it doesn’t always work the first time and is very hard on the environment. Herbicide which is generally weed killer can be diluted with water and can be effective control for air potato. A dilution of triclopyr, or glyphosate which is branded as Roundup are the most common. These herbicides are systemic (move throughout plant tissue) so care must be exercised to minimize damage to off target or surrounding areas. The least amount of chemicals introduced into the soil system is always the best policy.
A very important cultural and mechanical method to control the air potato is called the air potato roundup. Each year many counties in Florida, including Duval and Hernando (many other counties participate as well), recruit volunteers to help protect and conserve Florida’s natural areas via removal of air potato. During this roundup, citizens, organizations and local businesses get together to collect vines and bulbils. In 2003, the city of Gainesville collected 13 tons of air potato and other invasive plants (Gainesville Parks and Recreation). Air potatos are weeds and they generally invade open or disturbed areas – such as areas following a burn or cleaning mowing. A healthy ecosystem with good species diversity will help deter infestation.
The latest pest fighting “bio-control agent” that has been unleashed by the Florida Dept of Agriculture is the Leaf Beetle. It is a hardy, rapidly reproducing, flame colored wing against a black body as shiny as patent leather insect. The critter possesses a prodigious appetite, consuming by USDA estimates about 30 square feet of leaf in a three-month life span. They are being released throughout Florida to take measures to control the air potato invasion. These beetles are not to be considered “silver bullets” capable of eradicating any invasive plant at that, but they do promise cheaper, more environmentally friendly alternatives to chemical herbicides. The strangling air potato was brought to Florida as an ornamental plant, with its attractive heart shaped leaves in 1905. Thus since we have spent much time, money, and energy into controlling this invasive weed.