The Great Debate: Echinopsis or Trichocereus pachanoi?

Will the real San Pedro please stand up, please stand up…please stand up? Do a quick Google search of “San Pedro Cactus” and you’ll likely encounter two different scientific names: Echinopsis pachanoi and Trichocereus pachanoi. Science is supposed to be exact, so why would there be two scientific names for the same species of cactus? And which is the “real” one? The second question is a little easier to answer. Yes, both Echinopsis pachanoi and Trichocereus pachanoi refer to a San Pedro Cactus. In fact, they are technically synonyms and both are correct. Confused? It’s okay. Die-hard cactus lovers and even botanists have argued endlessly over the nomenclature of this species and we get it. There’s no synonym for Homo sapiens, so why should this be any different.

Before we dive into the scientific side of things, we want to take a moment to examine the history of this cactus and its common name. The San Pedro Cactus has ancient Andean roots, dating back thousands of years in South America. In fact, it can be traced back as early as 1500 BC, where it became known as Huachuma and was utilized in Chavin culture, the first Peruvian civilization. Shamans known as “huachumero” used it in spiritual, healing, and nature-related rituals as a way to get more connected with the spiritual and natural realms as well as one’s own consciousness. It is still used this way by shamans in many parts of South America today.

The name “San Pedro” has less honorable roots, related to the Spanish Invasion of Peru during the 16th century. With the Spanish colonization came a heavy Roman Catholic influence, and an effort to suppress some of the ancient spiritual traditions. In fact, the Spanish actively worked to stop people from utilizing the Huachuma cactus altogether. As is usually the case with most prohibition efforts, this didn’t result in rituals disappearing, but only caused the ceremonies to be performed in secret. Ironically, the cactus actually took on the name “San Pedro” in reference to St. Peter, one of Jesus’ apostles and an early leader in the Catholic church - who is believed to hold the keys to the kingdom of heaven.

In the Bible, Jesus actually tells Peter, “I will give you the keys of the kingdom of heaven; whatever you bind on earth will be bound in heaven” (Matthew 16:19). The San Pedro Cactus was named this way in reference to its ability for people to experience “heaven on earth” with its psychoactive properties.

So that’s how we ended up at our beloved San Pedro Cactus, but it still doesn’t answer our original question of which scientific name is “correct.” Trichocereus or Echinopsis? It doesn’t take a “genius” to see that each is a different “genus.” Echinopsis came first, with roots dating back to the 1700s. It is most commonly reserved for small, clumping cacti from South America. Trichocereus is a much newer genus (established in the early 1900s) and is a subcategory of the Cereus genus, referring to large, columnar cacti from South America.

Simply looking at the two descriptions, one would think that San Pedro would fall under the “large, columnar” description and would therefore belong to the Trichocereus genus. That person would be correct. The issue is that in 1974, a botanist known as H. Friedrich found that the seeds and flowers of Echinopsis and Trichocereus plants had no distinguishable differences and therefore should not be classified differently. And because Echinopsis came first, Trichocereus would be folded into the Echinopsis genus. So to call San Pedro part of the Echinopsis genus would also be…correct.

What does that mean for us? Well there’s a reason we’re not called “Echinopsis pachanoi source.” Besides the fact that it doesn’t exactly roll off the tongue, the main reason is that most people commonly know it as San Pedro and we think that both Echinopsis and Trichocereus names are valid. In fact, you’ll find both referenced on our site. We’ll let the old-time botanists battle that one out while we figure out the best way to sit on a fence. Our mission is to get you to the source for San Pedro Cactus - Trichocereus pachanoi, Echinopsis pachanoi, or whatever you want to call it!