This past Saturday Colombia’s President Juan Manuel Santos announced that he would be putting a stop to the use of a herbicide that has for decades been a fundamental part of U.S.-backed attempts to kill cocaine crops.

As glyphosate, the herbicide in question, is a known carcinogen, the president will look toward other ways of destroying the coca plants. In seeking an alternative to the cancer-causing herbicide, Santos is simply following the recommendation of the the Health Ministry, which has based its opinion on the World Health Organization’s decision to classify glyphosate as a carcinogen.

As reported by the Associated Press, Santos, while speaking at an event in the capital city of Bogota, said that defense and health officials should agree on a period of transition. As this transition is takes place, the spraying of the dangerous herbicide would need to be replaced with other methods, such as intensifying the “manual eradication” of coca plants.

Guardian reports Santos stated: “We must find strategies [to combat cultivation] that are more effective and cause less harm to the environment and public health.”

Alberto Gomez, the President of the Quindio Botanical Garden, has just proposed the use of a specific butterfly called the Eloria Noyeri to destroy coca crops in Colombia. As luck and nature would have it, the only two types of the 157 varieties of coca leaf that are grown to make cocaine just so happen to be the preferred food of this butterfly.

Kevin Whitaker, the U.S. ambassador to Colombia, stated that whether or not the herbicide would keep being used was a decision for Colombia and the U.S. government to make, and he would respect whatever that decision happened to be.

For the past two decades, more than 4 million acres of land in Colombia have been sprayed with the dangerous weed killer in an effort to kill the coca plants whose leaves produce cocaine.