Mark Mortenson, president and CEO of the Buffalo and Erie County Botanical Gardens. Photo courtesy Buffalo and Erie County Botanical Gardens Mark Mortenson, president and CEO of the Buffalo and Erie County Botanical Gardens, has died suddenly. The Botanical Gardens made the announcement on Sunday, Sept. 15. “Mark was a visionary leader who embodied the spirit of our ‘Wow, Wonder, Welcome’ philosophy, enriching the experience of every guest who visited our Gardens,” according to the announcement. “His warmth, generosity, and…