SALT LAKE CITY — Fireflies have been documented in 28 of Utah’s 29 counties. Despite that fact, most people say they’ve never seen one. Thompson Century Farm owner Diane Thompson Garcia said that’s probably because most people don’t go out into dark marshy areas at 10 o’clock at night in June. Garcia’s farm has been in her family since 1852. The farm, just under 24 acres, is home to a population of fireflies that have been documented to live there for the past 100 years.