We'll See How This Turns Out

From Scientific American:

Millions of sap-sucking psyllids (Aphalara itadori) will be imported into the U.K. to fight the Japanese knotweed (Fallopia japonica), an invasive species first introduced during Victorian times that has since become an ecosystem-choking threat. . . .

The knotweed has no natural predator in the U.K. but the psyllid, also known as jumping plant lice, is the knotweed's natural enemy in Japan, where the insect helps keep the plant in check. In fact, the psyllid eats knotweed exclusively. And according to tests conducted by the nonprofit Center for Agriculture and Biosciences International (CABI), the psyllid will not feed on any native plants. (Although it will, itself, be eaten by existing local predators.)

Japanese Knotweed is a major invasive weed in the US, too. It gets 10 feet tall and it prevents smaller plants from growing underneath it, so it is crowding out native wildflowers in many places. It develops a dense network of underground rhizomes that are very difficult to dig out, and even tiny fragments can grow into new plants. So the only available means of getting rid of it is herbicides.