Peasants say there are few alternatives to the cocaine trade.
Montoya will make his first appearance in a Miami federal court on Monday, the US justice department said in a statement.
“This extradition means the end of the Norte del Valle cartel,” Oscar Naranjo, national police chief of Colombia, said on Friday.
“All of its major leaders have been caught or killed.”
Montoya was captured last year in the Colombian region of Valle del Cauca after a long manhunt that ended when police raided his farmhouse and found him hiding in a ditch.
Another key Norte del Valle leader, Wilber Varela, was found shot dead in Venezuela early this year after a gunfight among rival smuggling organisations, while his brother, Eugenio, was also extradited to the US earlier this year on charges of cocaine trafficking, Reuters reported.
Colombia has extradited hundreds of drug suspects to the US, however exports of cocaine from the country remain at about 600 tonnes a year, the United Nations has said.
Colombia’s cocaine trade is now splintered among far smaller groups and most of the trade and the ensuing violence involves Mexican cartels.