Bean Leaves May Be Answer to Bed Bugs
By Chris Williams on April 17, 2013.
Do you know the story behind the invention of Velcro? It’s a case of technology stealing from Mother Nature. It all started back in 1941 with a Swiss engineer and his dog on a hunting trip in the Alps. When pulling the burrs off of himself and his dog, he took a closer look, trying to figure out how the seed heads managed to attach so aggressively. When he looked at the burrs under a microscope, he noticed the hundreds of tiny “hooks” that would catch on anything with a loop – like clothing, animal fur, or hair. He saw the possibilities—that two materials could be bound together by a system of synthetic hooks and loops. The rest is history.
Another plant with similar special characteristics may be the answer to our bed bug problem. Researchers were excited to discover that bean leaves trap bed bugs. The surface of bean leaves is covered with sharp, microscopic hooks called trichomes that are about 1/10 of the width of a human hair. When bed bugs step on bean leaves, the hooks impale them at leg joints where the cuticle is thinner. Struggling to get free just further ensnares them.
Actually, this isn’t a new discovery. It’s a bit of old folklore that no one paid much attention to—until now. Turns out bean leaves are an old remedy for bed bugs in Europe. In Bulgaria, Serbia, and other European countries, folks have been scattering bean leaves on the floor next to their beds for centuries. The leaves trapped migrating bed bugs at night and were burned the next morning.
It isn’t practical for most of us to scatter fresh bean leaves around our beds. The leaves dry out quickly and then no longer work and they can’t easily be applied in places other then floors. As you can imagine, researchers are looking to replicate the characteristics of bean leaves in the lab. They’ve made silicone rubber molds of the leaves’ trichomes, but so far the lab leaves have not worked as well. The researchers speculate that real trichomes manage to bend and twist more effectively to capture the bugs than do the synthetic versions.
More work is clearly needed, but if bean leaf anatomy could be used in a trap to control bed bugs, the discovery could be as important as Velcro. It took our Swiss engineer 10 years to synthetically recreate and perfect nature’s burr. The bean leaf scientists already have a patent on the technology, as well as a commercial backer. “Nature is a hard act to follow, said entomologist Michael Potter, “but the benefits could be enormous. Imagine if every bed bug inadvertently brought into a dwelling was captured before it had a chance to bite and multiply.”