In California, sales of legal recreational marijuana began with the new year on Monday, as about 100 dispensaries opened their doors in major cities. Under state law, adults 21 and over can possess up to an ounce of marijuana and can grow up to six plants at home. Marijuana sales are now allowed along the entire West Coast, including Alaska. Under federal law, marijuana remains a prohibited “Schedule 1” drug in the same category as heroin and LSD.