Shares of Innovative Industrial Properties (IIPR -20.54%), the country's leading cannabis real estate investment trust (REIT), were taking a dive today after it announced that PharmaCann, one of its biggest tenants, was defaulting on all 11 of its leases.As of 11:09 a.m. ET, the stock was down 20% on the news. Challenges continue in the cannabis industryThis morning, IIP said that PharmaCann, the nation's largest privately held and vertically integrated cannabis company, defaulted on its rent obligation in ...