Vern Greyn was standing in the raised bucket of a tractor in Dutton, Mont., trimming dead branches off a tree, when he lost his balance. He fell 12 feet and struck his head on the concrete patio outside his house in this small farming town on the central Montana plains.

Greyn, then 58, couldn't move. His wife called 911. A volunteer emergency medical technician showed up: his own daughter-in-law, Leigh. But there was a problem. Greyn was too large for her to move by herself, so she had to call in help from the ambulance crew in Power, the next town over.

"I laid here for a half-hour or better," Greyn says, recounting what happened two years ago from the same patio. When help finally arrived, they loaded him into the ambulance and rushed him to the nearest hospital, where they found he had a concussion.

In rural America, it's increasingly difficult for ambulance services to respond to emergencies like Greyn's. One factor is that emergency medical services are struggling to find young volunteers to replace retiring EMTs. Another is a growing financial crisis among rural volunteer EMS agencies: A third of them are at risk because they can't cover their operating costs.

Read more: NPR