In 2009, Montana's Big Hole staff began monitoring an invasive plant threatening native habitat. 17 years later, spotted knapweed estimates stood at just 8% of its 2012 peak, showing strong control

Managing invasive plants can require years of monitoring, treatment, and cooperation among land-management teams. At Big Hole National Battlefield in Montana, sustained efforts since 2009 have helped reduce a spotted knapweed infestation that threatened both the battlefield’s natural and cultural resources.

Seventeen years after monitoring began, found knapweed population estimates stood at just eight percent of their 2012 peak, indicating major progress in controlling the invasive plant.