Retired colonel Selahattin Güvenç (75), who lives in the Burhaniye district, has been achieving positive results from stevia (sugar herb) production that he started 14 years ago, and has begun shipping the seedlings he produced this year. Güvenç, who sent 50,000 stevia seedlings to Marmara Island in Balıkesir, said that stevia farming will now begin on Marmara Island.