Daily combat pitted U.S. soldiers against determined Communist forces in a challenging environment. Dense foliage could conceal large groups of the enemy. The U.S. military responded to the problem by assaulting trees and brush with a potent herbicide nicknamed Agent Orange. According to the Defense Department, more than 11 million gallons of the defoliant were sprayed on the jungles of Vietnam. 

"If they're spraying something to kill the foliage, hey that's a good thing because then I can see the enemy. I grew up on a farm, you can kill the weeds and about two or three weeks later the weeds are back, but the weeds didn't grow. But it wasn't colored. A lot of people think, well you woke up the next morning and the whole ground was orange. Agent Orange was colorless just like herbicides."

Agent Orange did its job. But it also had long-term side effects for those exposed to the defoliant, including various forms of cancer and Parkinson's disease.