In 1988, USDA scientists released flea beetles in North Dakota to fight a stubborn weed; their descendants spread across America and restored rangelands

In 1988, researchers working with the United States Department of Agriculture released a small population of European flea beetles onto infested rangeland near Valley City, North Dakota, hoping the insects might help control a plant that had been quietly overrunning the Northern Great Plains for decades. That plant was leafy spurge, an aggressive Eurasian weed that had already spread across more than two million hectares of pasture and rangeland in 35 American states by the time the beetles arrived.

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