Witch Hazel Howitzer

Plants use an incredible variety of methods to distribute their seeds. Witch hazel shrubs use one of the most impressive methods. Rather than relying on birds, animals, wind, or flowing water, witch hazels shoot their seeds. The system is so well-designed that in half a millisecond, the seeds shoot out of their pod at speeds up to 30 feet per second. This method had been described as a witch hazel howitzer.

The U.S. National Science Foundation supported researchers at Duke University in a study of the incredible method witch hazels use to scatter their seeds. The researchers studied various species of witch hazels, including those that have seeds lighter than a grain of rice and others ten times that weight. Their research shows that all species they studied sent seeds flying at the same velocities regardless of the seed’s mass.

The way this system works is that the woody seed pod dries out and deforms in a way that squeezes the seeds. The pressure builds until it pops, sending the seed flying. The director of the study, Justin Jorge, says it is like squeezing a watermelon seed between your fingers until it shoots out. The force built up by the witch hazel is enough to send seeds over large distances, allowing this plant to reproduce in a forest without the help of wind, birds, or running water.

We see design in the witch hazel’s seed dispersion method, and it reminds us of Romans 1:20, which says we can know there is a God by looking at the things He has made. We see that evidence in the vast variety of ways plants reproduce. We see plant seeds transported by wind. Some plants produce a fruit that birds or land animals eat, but the seeds pass unharmed through the animal’s digestive system. Some plants have seeds that stick to the fur of animals, and some animals intentionally bury seeds. Others attach a small nugget of nourishment for ants. The ants eat the food and discard the seeds far from where they found them. When none of these options are available, God has built plants that propel their seeds over a wide area, like a witch hazel howitzer.

— John N. Clayton © 2023

References: The National Science Foundation Research News for October 10, 2023, and Journal of the Royal Society Interface August 23, 2023.