Entomologists Richard Casagrande and Heather Faubert helped rid a Rhode Island farm of cypress spurge, an invasive weed, in the late 1990s.
"Then," says Casagrande (Univ. of Rhode Island), "along came swallow-wort.
is leading a team to help find biocontrol foes to take on swallow-wort, research backed by Northeast IPM Partnership
"They stopped eating after a single bite," says Casagrande
Working off a TAG (technical advisory group) test-plant list approved by the USDA's Animal and Plant Health Inspection Service, Casagrande's
team examined five possible biocontrol specialists in their quarantine lab, including two moths that evolved to feed on swallow-wort leaves.
The researchers wanted to be sure these biocontrol insects wouldn't jump to plants on the TAG list, since the last thing anyone wants is a new pest dominating the landscape.
"No-choice" tests ensure guests you want
The TAG list includes, naturally, most native milkweed relatives and even their sixth cousins.
"Luckily, none of our native plants are closely related to swallow-wort," says Casagrande
Both leaf-eating moths "passed the acid test," says Casagrande