The green rush is here.

More than 20 states have approved marijuana use for medicinal purposes and Colorado and Washington are opening up the plant for recreational use. Marijuana companies rose more than 50 percent in 2013 and opened 2014 with a bang, rising almost 150 percent in just three weeks.

This list gives an overview of publicly traded marijuana stocks worth over $50 million, including hydroponic companies, vaporizer producers and research houses for medicinal purposes. Note that most are small and trade over the counter, which means extra risk to go with that potential growth: