In early January, Keith Elwell was doing one of the things he does best, swinging chainsaws to help save forests from wildfire. Amid groves of junipers and white oak trees, Elwell led a team of a half-dozen volunteers, clearing brush and dead limbs in Twin Springs Preserve in Williamson County, Texas, a 170-acre county preserve a 40-minute drive north of downtown Austin.

Set on the northeastern edge of Hill Country, a rolling, rocky landscape of natural springs and wild grasses, it’s also adjacent to Georgetown, the fastest-growing city in the United States according to US Census Bureau data. Once a small farming town, it’s now an Austin suburb of more than 75,000 people with 60 subdivisions under construction.