In 1973, Montana released a gall fly to control spotted knapweed; decades later, the biocontrol program was linked to over 3 times more hantavirus-positive deer mice
A biological control project started half a century ago to destroy a stubborn invasive weed accidentally set off an ecological chain reaction that increased human exposure to a deadly virus. In 1973, wildlife officials and agricultural scientists in Montana released two species of European gall flies, Urophora affinis and Urophora quadrifasciata, to control the spread…