As we worked on the invasive species in english class, I had to study one of these species. Mine was the Hemlock woolly adelgid. It's an invasive insect of hemlock trees. It's like an insect similar to the aphid. It measures 1 mm long. Adelgids were first introduced in Virgina through the importation of japanese hemlock trees.To fight against these, the scientists has been using (since 2004) a predator beetle. As ladybugs for aphids, these black beetles feed specifically on hemlock woolly adelgids (they eat eggs, larvaes and adults). Nevertheless, the scientists think that it was not sufficient because the adelgid reproduces very quickly and the predator beetles take a number of years to build their population. As they reproduce so rapidly, the scientists decide to put a chemical product in addition to the predator beetle. Both permit to prolong the life of the trees and reduce the adelgid population.