Folk remedy scientifically proven to repel mosquitoes
By Julie Deardorff
Mosquitoes are formidable foes. Researchers have tried inducing anorexia to starve them to death, creating genetically modified strains and using catnip and tomato-based substances as repellants.
Now a traditional folk remedy best known among those in Mississippi’s northeast hill country has proven to be an effective way to repel the pesky creatures, a welcome alternative to those who want to avoid the harsh chemical DEET.
Three chemicals found in berries and leaves of the American beautyberry plant, Callicarpa amerciana, repulse mosquitoes known to transmit yellow fever and malaria, according to a 12-month study by scientists at the National Center for Natural Products Research at the University of Mississippi.
While mosquitoes carrying West Nile virus were not tested as part of the study, the United States Department of Agriculture-Agriculture Research Service has filed a patent application to use one of the chemicals in the plant-callicarpenal-as an arthropod repellent.
The folk remedy piqued the interest of scientists after ARS botanist Charles Bryson told his colleagues how his grandfather would use fresh, crushed leaves of American beautyberry to help keep biting mosquitoes away from
draft animals such as horses and mules. Placing the mashed leaves under an animal’s harness would produce a repellent oil.
For the last 40 years, Bryson has been anecodotal proof that crushing a handful of leaves on skin keeps away mosquitoes, deerflies and horseflies. His colleagues at the ARS were able to confirm the natural remedy
DEET, developed by ARS and the U.S. Army decades ago, is the most commonly used insect repellent. But nepetalactone, the essential oil in the catnip plant, is about 10 times more effective at repelling mosquitoes than
DEET, the compound used in most commercial products according to some studies.
In addition, while the EPA has found normal use of DEET isn’t a health hazard, products using high concentrations shouldn’t be used with children. And researchers at Duke University found that extensive use of DEET caused brain-cell death and behavioral changes in animals.
The beautyberry, considered one of the best shrubs to grow in southern Illinois according to the University of Illinois Extension, produces white flowers in the summer. In the fall, the stems bear blue, white, purple
and pink clusters of little fruit. It blooms and fruits on new growth.