If one is out hiking somewhere in the southeast United States, watch out, as this YouTube video shows:
The video displays a plant moving around “on its own,” apparently without the aid of wind or external force.
“OK that is really starting to creep me out,” Jason Freeman, who filmed the incident. “It’s not wind. Look at it go.”
Freeman was in South Carolina with his wife when the plant began shaking. After the video was published several months ago, some claimed there were paranormal reasons behind it.
But there might be a better explanation.
“This happens when a plant’s resonant frequency is magnified by wind that we can’t feel,” wrote one YouTube user, referring to a piece in the American Journal of Botany titled “Oscillation frequencies of tapered plant stems.”
The user added: “The key, it found, was extremely weak winds that are imperceptible to humans, but magnify oscillations in the plant, making it appear to move for no reason.”
According to MailOnline, the 2001 study said this:
A 2001 study in the American Journal of Botany titled ‘Oscillation frequencies of tapered plant stems.’ examined the phenomenon of plants that appear to sway on their own.
The key, it found, was extremely weak winds that are imperceptible to humans, but magnify oscillations in the plant, making it appear to move for no reason.
“Free oscillations of upright plant stems, or in technical terms, slender tapered rods with one end free, can be described by considering the equilibrium between bending moments in the form of a differential equation with appropriate boundary conditions,” the researchers Hanns-Christof Spatz and Olga Speck wrote, before analyzing the forces needed to the bizarre phenomenon.