The purple-flowered Knapweed is a particularly troubling invasive species to western farmers. Indeed, since first being introduced from Europe last century, it has been known to choke up to one hundred percent of many western cattle ranges and leave them useless for grazing. Fortunately, conservationists have called upon another foreigner to combat it — the Cyphocleonus achates, or more simply, the root weevil. This insect, about an inch long and speckled in brown and grey, lays its eggs on the roots of the knapweed where its young feast on and weaken the plant. Already a hero in Europe and Asia, this weevil is expected to also become a welcomed guest to many a western rancher.

Author