Tuesday, March 24, 2009

Devil's Heads!

“Mr. Jay, what is this?” It’s a common question when a student hands me a water chestnut. The water chestnut, dark in color and full of pointy spikes, triggers the imagination like few other objects which appear on our beach at Beczak. “Could it be a sharks tooth, or maybe an egg?” “How did it get here?”

While the story of the water chestnut isn’t quite as exciting as what it generates in the minds of our students, it is still an interesting find. The species that we see in the Hudson River is the European water chestnut (Trapa natans). This invasive plant found its way into the Hudson River in 1884 possibly as an introduced source of food for waterfowl or an escaped plant from a water garden. The water chestnut grows in fresh water and may quickly overspread native plant species. This has the potential to alter the Hudson River ecosystem.

If the water chestnut grows in fresh water, how do we find the nuts here in Yonkers, where the water is brackish? The answer is simple – the tides. In fact, the tides will carry the floating chestnuts all the way to the beaches of Sandy Hook, NJ where swimmers will painfully step on them. Consequently, the locals like to refer to them as Devil’s heads!

Jason Muller
Educator/Technology Specialist