You're probably aware how hot the U.S. marijuana industry is. Thirty-three states have now legalized medical marijuana. Ten states allow the legal use of recreational marijuana. Several top U.S.-based marijuana stocks more than doubled in value last year. But how much do you know about marijuana-related jobs in the U.S.?

Glassdoor, one of the world's leading job and recruiting websites, released a detailed study of jobs in the U.S. cannabis industry on Jan. 30, 2019. This report revealed a lot of information about the state of marijuana jobs in the country. Here are four surprising things from the Glassdoor report that you probably didn't know. 

Hands holding scissors to trim cannabis plant.

Image source: Getty Images.

1. Hiring in the U.S. has soared 76%

The biggest story from the Glassdoor report is that marijuana industry employers are hiring in a major way. Glassdoor's analysis found that the number of job openings in the U.S. cannabis industry soared by 76% year over year as of December 2018. Digging into the details of the Glassdoor study reveals that hiring accelerated in the second half of 2018. 

Granted, the actual number of job openings in the report wasn't huge -- slightly over 1,500 openings in November and December of last year. And these figures are only from an analysis of Glassdoor's jobs database and don't include other sources. However, Glassdoor's findings point to the jobs market in the U.S. cannabis industry heating up significantly.

2. Cannabis jobs pay very well

When you think about marijuana-related jobs, pictures of entry-level workers making the minimum wage might come to mind. But that's not what Glassdoor found in its study.

The median base salary for cannabis jobs in Glassdoor's database was $58,511 per year. That's 10.7% higher than the overall U.S. median base salary. Around 30% of the current job openings in the U.S. cannabis industry paid $70,000 or more annually. 

3. Several top markets for job openings aren't in states with legal recreational pot

Since California claims the largest marijuana market in the U.S., it only makes sense that California cities dominated the top markets for hiring in the cannabis industry. San Francisco and Los Angeles ranked at the top of the list, with Riverside, San Jose, Sacramento, San Diego, and Santa Barbara also ranking among the top 15 markets for marijuana-related job openings. 

However, several top markets for job openings were in states that have only legalized medical marijuana. New York City ranked No. 4 on the Glassdoor list. Chicago came in seventh, with Miami-Fort Lauderdale, Florida, in the No. 8 position.

4. Several of the top hirers are publicly traded

Canadian marijuana stocks get the most publicity, but there are more publicly traded U.S. marijuana businesses than you might think. Three of them made Glassdoor's top 15 ranking of employers hiring for cannabis jobs.

Green Thumb Industries (NASDAQOTH:GTBIF) ranked as the No. 1 cannabis industry hirer in Glassdoor's report. The Illinois-based company operates cannabis production facilities and retail cannabis stores in nine states. The biggest U.S. cannabis retailer, MedMen Enterprises (NASDAQOTH:MMNFF), came in seventh.  

Trulieve (NASDAQOTH:TCNNF) ranked No. 12 on the Glassdoor list. The company is technically headquartered in Toronto, Canada, but it operates dispensaries in Florida, California, and Massachusetts.

At least one employer on Glassdoor's list doesn't trade publicly but could be available as an option for investors relatively soon. Medical marijuana business Columbia Care, which took the No. 15 spot on the Glassdoor ranking, is finalizing a merger with Canaccord Genuity Growth Corp., a special-purpose acquisition company (SPAC). SPACs allow public investors to invest on stock market exchanges in private companies. The transaction will value the merged companies at $1.35 billion. 

What does this mean for investors?

The fact that more employers are hiring in the U.S. cannabis industry doesn't necessarily mean that the stocks of the companies hiring the most are great picks for investors. It doesn't even mean that investing in any U.S. marijuana stock is a smart move.

However, Glassdoor thinks that increased hiring could be a sign of greater legitimization of the U.S. cannabis industry. That conclusion seems logical. Companies that hire aggressively are likely to be relatively confident about their future.

Further legitimization of the cannabis industry should attract more investors who have remained on the sidelines with marijuana stocks so far. Again, this doesn't mean that Green Thumb, MedMen, or Trulieve are necessarily marijuana stocks to go out and buy right now. But it should be good news over the long run for investors hoping to profit from the U.S. marijuana boom.

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Editor's note: A previous version of this article stated that Columbia Care would conduct an IPO. The article was corrected to state that the company is merging with Canaccord Genuity Growth Corp. in a transaction that would allow it to be available to stock market investors. The Fool regrets the error.