A Northwest Youth Corps crew removes invasive false indigo bush from Hamilton Island in 2014. The bush has potential negative impacts on native plant species including Columbia yellowcress, which is listed as threatened in Washington State. (Photo by Tim Darland, Bonneville Lock and Dam Project) [District pest plan focuses on early detection, rapid response]

A Northwest Youth Corps crew removes invasive false indigo bush from Hamilton Island in 2014. The bush has potential negative impacts on native plant species including Columbia yellowcress, which is listed as threatened in Washington State. (Photo by Tim Darland, Bonneville Lock and Dam Project)

A Northwest Youth Corps crew removes invasive false indigo bush from Hamilton Island in 2014. The bush has potential negative impacts on native plant species including Columbia yellowcress, which is listed as threatened in Washington State. (Photo by Tim Darland, Bonneville Lock and Dam Project)