These Trunk-Wearable "Tree Fitbits" Provide Data That Could Prove Valuable for Agriculture
Accelerometers strapped to tree trunks prove able to pinpoint various changes, and could prove vital for future climate change monitoring.
A team at the University of Colorado, Oregon State University, and the US Geological Survey have come up with a novel wearable for environmental monitoring — but it's trees, not humans, who wear this particular Fitbit-inspired device.
"“Accelerometers are in cars, smartphones and Fitbits — they track movement in real time. When we put them on trees, accelerometers detect vibrations on the trunk as the tree sways in the wind," explains Deidre Jaeger, PhD and lead author of the study into the unusual trunk-borne devices. "That sway corresponds to the tree's mass, which tells us what the tree is doing."
How a tree moves, the team explain, can offer considerable insight into its health and environment — its mass changing according to water uptake. While previous at building a Fitbit for trees have recovered relatively limited data, typically regarding gross changes like when a tree sheds its leaves in the fall, the team's latest work shows how it can pick up considerably more detail — right down to the moment when a white ash flowers and releases its pollen.
"Previous work suggested trees would need to be out in the open to have enough wind to sway," Jaeger explains, "but we found it not only works on trees inside a city — it’s actually an ideal way to track urban tree growth. Accelerometers are discrete, continuous and unaffected by the action or physical barriers a city environment presents. We get high-res, reliable data.
"Now that we know accelerometers can determine flowering dates that could be useful in agriculture, predicting when tree fruit may ripen or knowing when to apply interventions to protect tree buds from extreme weather," Jaeger adds.
"Trees are also bioindicators of climate change. So having high-resolution, long-term accelerometer data would help scientists better anticipate how a changing climate will impact tree bloom, tree health and beyond"
The team's work, which strapped two commercial solar-powered accelerometers to a pair of white ash trees and monitored the data over a period of time, has been published in the journal Agricultural and Forest Meteorology under closed-access terms.