When exploring cannabis strains, you’ll probably notice them sorted into three groups: indica, sativa, and hybrid. The belief that each one delivers distinct psychoactive effects (indicas relaxing, sativas uplifting, hybrids somewhere in the middle) is so deeply rooted that it’s the starting point for strain recommendations in many dispensaries.

But scientifically speaking, this is a broad view with little basis. There’s no evidence to suggest that these species exhibit a consistent pattern of effects – not all indicas will sedate you, and not all sativas energize. The only thing consistent about them is their grow patterns (indicas short and stout, sativas tall and narrow), meaning their distinction is only really useful to cannabis cultivators.

What’s more, we can’t even be sure there’s such a thing as “pure” indica or “pure” sativa, or that strain names we’re familiar with always contain consistent blends of the two.

So how did all these terms find their way into mainstream cannabis culture? Why are there so many? And if indica and sativa don’t indicate effects, then what on earth does?

The Facts and the Fiction

Indica and sativa labels were first introduced to cannabis consumption largely for convenience. With so many strains to choose from, the plant’s genetic heritage helps narrow things down, especially if you’re new to medical cannabis.

This rule of thumb isn’t totally wrong, but it’s not the most accurate. It’s better to think of cannabis on a spectrum of sativa-ness and indica-ness.

Strain names help achieve this to an extent, by indicating unique genetic blends of indica and sativa plus any additional tweaks. It’s important to note: There are so many variances to batches of strains that the indica-sativa ratios you see in store rarely match the bud’s exact genetic makeup. However, a general understanding of a strain’s heritage can provide a general idea of what to expect when trying something new. You can get more granular later.

To begin with, though, you may be wondering:

Why Are There So Many Strains?

Medical cannabis patients have access to many strains with a full range of therapeutic benefits. Cannabis experts have identified at least 2,300 of them. That’s thanks to generations of experimentation to bring out the best attributes of the plant.

In fact, the true number of strains may be much higher, since new ones continue to pop in and out of existence all the time. When a cannabis cultivator discovers a new strain, they’ll make it more marketable by giving it a creative name. If the strain takes off, it’s eventually recognized as legitimate like those most of us know and love; if it fails, it might just disappear.

But references like Granddaddy Purple and Lemon Skunk aren’t just marketable – they’re also necessary because of cannabis prohibition. The illicit nature of cannabis consumption (in the eyes of federal law) has made it difficult to standardize the creation, naming, and registering of new strains.

Nonetheless, this is an important process that allows us to optimize combinations of characteristics for unique needs. We just need a more accurate way to describe them – and the answer is cannabinoids and terpenes.

Choosing Cannabis Accurately

Using cannabinoid content and terpene content to describe effects is how medicinal growers do business behind the scenes. For example, instead of selling Purple Kush, they’d call it Bedrobinol, which contains highly standardized amounts of the cannabinoids THC and CBD. It’s not as fun, but at least you know what you’re getting, which is key for medical cannabis consumers.

Going forward, experts think, we need more rigorous genetic testing and standardized creation to fully understand a strain’s effects. This will come as cannabis becomes more acceptable.

On the patient’s part, that understanding will come with a little trial and error. But at least there’s no shortage of strains to try, and the diversity of cannabis is what makes it such an exciting tool for all.