Officer Jeremy Veach's dash cam captured the strange accident on video after he pulled over motorist Candice Duffey for driving without having her headlights on.
Veach was not seriously injured by the tree, but did receive three stitches. Duffey's SUV took the bulk of the impact.
"I was picking tree bark out of my hair -- it was in my ears," Veach told KCCI. "It could have been a lot worse than it was."
According to Veach, the base of the tree appeared to be rotten, which is likely what caused it to topple over.
Duffey did not receive a ticket after the tree damaged her car.
"That's the one, true way to get out of a ticket, ya know," Veach said. "Everyone asks a police officer, 'How do you get out of a ticket?' If a tree falls on you, you're probably going to get off."