Last year, bitcoin made investors go on a mad rush and this year, it’s marijuana stocks’ turn. This is especially true against the backdrop of more legalization of the plant for recreational use.In the United States, nine states and Washington, D.C., have currently legalized recreational marijuana, while 29 states have legalized medical weed. Canadians will also be able to buy and consume cannabis legally, effective Oct 17. The move made Canada the second country in the world to legalize the drug for both medical and recreational use, trailing Uruguay, and the first country among G-7 nations (read: Canada Legalizes Marijuana: Two ETFs to Tap the Boom).Growing legalization of recreational or medical marijuana has paved the way for a merger mania, spurring a large number of deal activities in the industry. The most notable among this is the beer and spirits giant Diageo DEO, which is in talks with three Canadian pot producers for buying a stake or forming a partnership to produce cannabis-infused beverages. An international producer and beer marketer Constellation Brands STZ invested $3.8 billion last month to increase its stake in Canopy Growth CGC, the biggest marijuana industry deal so far.Molson Coors TAP) is also starting a joint venture with Hydropothecary to develop marijuana drinks in Canada while Heineken HEINY owned Lagunitas launched a THC-infused sparkling water in California dispensaries on Jul 30 (read: Pot Stocks Are on a High: Play These Cannabis ETFs).According to the Arcview Market Research, the U.S. legal cannabis market is projected to reach $11 billion in consumer spending this year and more than $23 billion by 2022. Per an analyst at Cowen, the U.S. legal cannabis industry is expected to reach $75 billion in sales by 2030, surpassing the carbonated soft drink market in 2017.How to Play?Given this, investors seeking to ride the ongoing green rush may want to tap the space. For them, we have highlighted a few ETFs and stocks that could be compelling picks.ETFMG Alternative Harvest ETF MJThis is the first and only pure ETF targeting the cannabis/marijuana industry. It tracks the Prime Alternative Harvest Index, designed to measure the performance of companies within the cannabis ecosystem, benefiting from global medicinal and recreational cannabis legalization initiatives. The fund holds 37 securities in its basket with double-digit concentration on the top two firms. Canadian firms make up 61% of the portfolio, while American firms comprise just 21%.The ETF has AUM of $562.3 million and trades in a good volume of around 304,000 shares. It charges 75 bps in annual fees and has climbed 16.2% in the year-to-date timeframe (read: 4 Sector ETFs That Beat the Market in August).AdvisorShares VICE ETF ACTAnother way to play the upcoming boom in the marijuana industry is with ACT. It not only targets the cannabis industry but also offers concentrated exposure to “vices” including alcohol and tobacco. The fund invests in companies that derive at least 50% of their net revenues from the marijuana and hemp industry or have at least 50% of their company assets dedicated to lawful research and development of cannabis or cannabinoid-related products.Specifically, the fund has 19% exposure to cannabis-related companies. It is an actively managed fund and has attracted $13.2 million in AUM since its debut in mid-December. The ETF has 0.75% in expense ratio and trades in lower average daily volume of nearly 5,000 shares. It is up 1% in the year-to-date timeframe.Cara Therapeutics Inc. CARAThis biopharmaceutical company is focused on developing and commercializing new chemical entities designed to alleviate pain. It has a market cap of $814.88 million and its earnings are expected to grow 1.39% next year. The stock has soared 70.3% in the year-to-date time frame and has a Zacks Rank #3 (Hold).Cronos Group Inc. CRONThis company is engaged in the investment in firms which are licensed to produce and sell medical marijuana. With a market cap of $2.12 billion, the stock has an estimated earnings growth of 750% for the next year. It has surged 22.9% so far this year and carries a Zacks Rank #3 (read: 5 Best Stocks of the Top ETF of August).GW Pharmaceuticals GWPHThis is a biopharmaceutical company focused on discovering, developing and commercializing therapeutics from its proprietary cannabinoid product platform in a broad range of disease areas. The company has an estimated earnings growth rate of 22.17% for the next fiscal (ending on September 2019). It has a market cap of $3.88 billion and has gained 6.7% so far this year. GW Pharmaceuticals currently has a Zacks Rank #3.Want key ETF info delivered straight to your inbox?Zacks’ free Fund Newsletter will brief you on top news and analysis, as well as top-performing ETFs, each week. Get it free >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Diageo plc (DEO): Free Stock Analysis Report Constellation Brands Inc (STZ): Free Stock Analysis Report Heineken NV (HEINY): Free Stock Analysis Report GW Pharmaceuticals PLC (GWPH): Free Stock Analysis Report Cara Therapeutics, Inc. (CARA): Free Stock Analysis Report Canopy Growth Corporation (CGC): Free Stock Analysis Report Cronos Group Inc. (CRON): Free Stock Analysis Report ADVSR-VICE ETF (ACT): ETF Research Reports ETFMG-ALT HRVST (MJ): ETF Research Reports To read this article on Zacks.com click here. 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