To those outside of the cannabis industry, judging marijuana strains may seem like the kushiest job in the world. And also, an impossible one.

How does someone smoke their way through a buffet of hundreds of different types of weed? After hitting a few different joints, don’t they blur together into one blissful (or terrifying) high? And does the last strain you smoke always win?

According to Nikki Lastreto and Swami Chaitanya, it’s more complicated than you’d think. They’re a pair of veteran cannabis farmers who for the last 16 years have served as judges at the Emerald Cup, a festival in Sonoma with a serious competition element where growers submit the cream of their crop to be evaluated and ranked. This year there were 10 voting judges, ranging from concentrate makers to dispensary owners. The group met three times (plus smoking a few as homework).

“It’s an honor to judge,” says Chaitanya. “You look out at this sea of jars, and you can just sample all the best. It’s really a delight.”

“It’s a real challenge,” adds Lastreto. “We are looking for the most unique, and we’re looking for something that’s sophisticated. Something that’s complex, that won’t just knock you in the head.”

Although they receive roughly 200 entries, the majority can be weeded out before the smoking even begins based on look and smell. Judges put aside their favorites, then they compile a top tier judged on a 50 point system: 10 points each for looks, flavor and fragrance, with 20 points for effects.

“You break open the bud and stick your nose right into the middle to find the tastes and aromas in there. Is it cardamom, moth balls, new sneakers, Pine-Sol, lavender? These are the terpene profiles,” says Chaitanya.

Unlike wine, there’s no way to spit out samples to avoid the cumulative effects of trying dozens of varieties of weed. Which is to say, judges do get very, very stoned.

“We smoke all year long to stay in shape. It’s like spring training. We have to stay on that level,” says Chaitanya.

But a key difference between cannabis and wine is that with alcohol, the type of intoxication doesn’t really differ much.

“You’re not going to get a different type of drunk. It’s not going to be so much different if it’s a cabernet or merlot. But with cannabis, it’s very different, a lot of that comes from the terpene profile and the ratio of CBD and THC,” says Lastreto.

“Drunk is drunk, but one of the key things about cannabis is what is you’re feeling. How are you elevated? Whether it’s social and everyone’s giggling, or you want to get up and do your chores in the morning. And that’s why we revere it so much. That’s why we do have to smoke it,” adds Chaitanya.

As cannabis has become more mainstream, the entries have naturally changed. Now testing prevents use of pesticides or inorganic fertilizers. Look and smells have both improved. Although cannabis potency has skyrocketed, the most powerful strains don’t typically take the crown. And naturally, the judges’ palates have become more nuanced, with most able to identify the names of ten or fifteen terpene profiles, which vary in popularity.

“A few years ago, the smell of diesel was very popular. Then it switched to something more fruity, everyone wanted pineapple. This year we had a lot of fruity entrants,” says Lastreto.

There’s typically a consensus on the top couple of entries, but debate on the winner is never so simple.

“I will tell you that the top two winners, we spent a couple hours trying to figure out which was number one,” says Lastreto.

See the full list of Emerald Cup winners here

Dan Gentile is a digital editor at SFGATE. Email: Dan.Gentile@sfgate.com | Twitter: @Dannosphere