MYRTLE, TEXAS. Myrtle, originally known as Myrtle Turf, was two miles south of Houston in what became the Pierce Junction oilfield in southern Harris County. A Myrtle Turf post office operated from 1839 to 1843. The community reported a population of 153 in 1940, when it was on the International and Great Northern line. By the 1980s only scattered dwellings remained at the townsite.