What is in this article?:
- Unwelcome visitors: Biological control for invasive pests
- Pre-screening work
- Followed up with midge
- Check on safety
• The latest example is the release of beneficial beetles to target air potato vine, an “aggressive, invasive exotic plant that is displacing native plant species and disrupting ecological functions throughout Florida,” according to the USDA-ARS.
MELALEUCA, a prolific seed producer
Followed up with midge
“However, that one failed, and we followed up with a midge, which looks like a mosquito. It lays its eggs in the growing tips and produces stem galls. That one has been extremely effective.
“Between that combination of insects, we’ve cut way back on seed production. If it does produce seed and they germinate, many of the insects will attack those young seedlings. If the seedlings manage to survive, the insects stunt their growth so they can’t go anywhere.
“It has proven to be a very effective project — but only when integrated with the other management practices. The insects don’t remove the trees and there’s all this wood out there that must be taken out. But the biocontrol program has made that process much more effective.”
The air potato vine…
“Air potato vine is one of the things we’ve been working on recently and it’s the latest biocontrol agent we’ve released. Our first release was in cages last fall. The first open release was last March.
“Air potato is a lot like kudzu — it grows over the tops of trees and blankets everything. It cuts down on light, kills the understory and is particularly bad in conservation areas.
“In the spring, it sprouts from things that look like small potatoes. Those produce vines that can grow eight inches per day. They go straight up whatever vertical surfaces are available.
“During the summer, they usually overtop trees and then, in November, they’ll die back. As they die back they pump their resources into more of the potato-like structures (also known as ‘baubles’). Those will then drop to the ground and the next fall they’ll sprout and begin the process all over again.
“We’re working with two insects — both leaf beetle types — to deal with this plant. One leaf beetle feeds on the vine itself and defoliates it. That cuts down on the resources the plant has to produce baubles. We’re hoping the bauble production will really drop off after we release them.