They are small but mighty.
A new species of air potato beetle is being reared and released in Florida to wage war against the invasive air potato vine.
First, a little background on the enemy.
The air potato vine was introduced in Florida in the early 1900’s and has since spread to every county. It has invaded both urban and rural; managed and natural areas alike. This vine can quickly overtake our native flora as it grows up to eight inches a day. Native trees and shrubs are smothered as their access to sunlight is blocked. This reduces the amount of food available for our native insects and birds, and on up the food chain the effects ripple. Air potato vine disturbs natural ecological processes by acting as a fire ladder. During forest fires, the vines allow fire to reach up into tree canopies. Trees that normally could withstand a ground fire can be damaged or destroyed when infested with air potato.
Air potato vine is very difficult to manage because it makes potato-like bulbils along the stem. New plants sprout in the spring from bulbils that were dropped to the ground. Bulbils make the plant difficult to control even with herbicides. The best control method unfortunately involves a shovel and sweat.
The O.G. Biocontrol Beetle
As many gardeners know, Lilioceris cheni, the air potato beetle, was released into Florida for control of air potato vine back in 2012 after extensive research to ensure it would not inadvertently cause harm. L. cheni has since been dutifully munching on air potato leaves for over a decade. The vines and bulbils are reduced in size because of their feeding. This has slowed down the invasion, but not stopped it, because L. cheni won’t eat those troublesome bulbils.
Enter our unassuming insect hero- Lilioceris egena. This species of air potato beetle, native to China and Nepal, looks identical to its cousin, L. cheni, but their larvae feed exclusively on air potato bulbils. The female beetle lays about 900 eggs in her lifetime on the bulbils. Her eggs hatch in about five days and the larvae voraciously eat the bulbils until the insides are liquified and destroyed.
Research was conducted with eighty-two plant species in forty-six families to ensure that the eggs are only laid on air potato and no significant damage is done to off-target plant species. They are now being reared for release as a part of the air potato biological control program, a group effort of the FDACS Division of Plant Industry (FDACS-DPI), the U.S. Department of Agriculture’s Agricultural Research Service (USDA-ARS) and Animal and Plant Health Inspection Service (USDA-APHIS), and the University of Florida’s Institute of Food and Agricultural Sciences (UF/IFAS).
You can now request a shipment of these new, cute-as-a bug, weapons in the fight against the invasive air potato vine on your property. Visit the FDACS website and click the Air Potato Report Form button. You will be asked to rank your infestation level as low, medium, or high. They also want to know how frequently you spray for mosquitoes, and what other control methods you have used on your vines in the past, if any. Supplies of Lilioceris egena are limited, and you are not guaranteed to receive them. However, the beetles will be released within a ten-mile radius of every reported infestation.
The original release of the air potato beetle in 2012 has been a success story in the biological control of invasive plants. This new species is an exciting advancement and offers great promise for our beautiful Florida natural areas.
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