Oregon class project could lead to technology that will save lives of skiers trapped in tree wells.

Avalanche beacons have long been a gold standard for backcountry safety, but a team of engineering students in Central Oregon is developing a new piece of tech to tackle a different, often invisible winter threat: tree wells.

What began as a classroom project at Oregon State University’s OSU-Cascades campus has evolved into the Tree Well Guardian, a wearable safety device designed to alert search-and-rescue teams when a skier or snowboarder becomes trapped upside down in deep snow.

The Hidden Threat of Tree Wells

While avalanches dominate winter backcountry headlines, tree wells represent a silent danger that can quickly turn fatal.

What is a Tree Well?

A tree well forms when heavy snow accumulates around the outer branches of a tree but fails to pack down near the trunk. This creates a deep, hollow pocket of loose snow and air masked by low-hanging limbs. If a skier or rider falls into this depression, they frequently land headfirst, triggering snow-immersion suffocation (SIS) as loose snow caves in around them.

For creators Makani Hiltner and Hunter Erhard, the motivation to build a solution was close to home.

"The idea first kind of came about when Makani and I were having a conversation about some of the recent deaths that had taken place up at Mount Bachelor that were tree-related," Erhard explained, noting that inspiration also came from a shared family connection. "Actually, both of our dads had said something to us about why isn’t there some kind of device that would help with tree wells or people dying in tree wells."

How the Tree Well Guardian Works

The experimental device is designed to be strapped directly to a rider's ski boot or snowboard binding. It relies on internal orientation sensors to recognize when a user is inverted—the primary position of a dangerous tree well immersion.

To prevent rescue teams from chasing accidental triggers, the students engineered a strict, multi-tier failsafe protocol:

[Inversion Detected]

│

▼

[10-Second Countdown] ──(User cancels?)──► [Alarm Disarmed]

│ No

▼

[Auditory Beep Warning]

│

▼

[Second 10-Second Windows] ──(User cancels?)──► [Alarm Disarmed]

│ No

▼

[Emergency Alert Broadcasted via GPS & Companion App]

“If you are flipped upside down, representing a tree well immersion, it would give you 10 seconds to turn it off so we would avoid any false alarms,” Hiltner explained. “It would give you a beep. That lets you know that it’s gonna enter the alarm mode, and then it would give you another 10 seconds to let you turn it off again."

If the two countdown windows pass without user intervention, the device automatically broadcasts an emergency distress signal complete with exact GPS coordinates.

Moving Toward Production

The final iteration of the Tree Well Guardian is projected to be roughly the same size as a standard avalanche beacon. The engineering team is also developing a companion smartphone application to assist partners and rescue personnel in tracking the distress signals in real time.

By automating the SOS process for a trapped, immobilized rider, the OSU-Cascades students hope to bridge the critical time gap between a deep-snow burial and life-saving intervention.