Lawn & Garden
AUBURN UNIVERSITY, Ala. – What is this white fuzz taking over plants in window boxes or planters? It’s not a spider web, so what is it?
According to Alabama Extension Entomologist Katelyn Kesheimer, the mysterious white fuzz is actually a group of planthoppers. Planthoppers are piercing-sucking insects that use their straw-like mouthparts to feed on plant sap.
Adult planthoppers have a protective waxy substance that covers their body and provides protection.
“All insects have a wax layer on the outside of their exoskeleton that helps them retain moisture inside their body and repel any additional moisture outside of their body,” Kesheimer said. “However, some insects require additional protection from a waxy coating to protect them from their environment.”
This is where the white fuzz comes in for planthoppers. The adult planthoppers have white, waxy protrusions that help move sugary liquid away from their body as they defecate. On the other hand, immature planthoppers have wax glands on their body that allows them to produce the fuzz.
The fuzz is easily left behind on plants or other insects that come into contact with the planthoppers. While it is not harmful to humans or insects who may come into contact with it, it can appear unsightly on ornamental plants.
The waxy layer and fuzz protects planthoppers from not only predators, but themselves.
“The small bugs can be hidden underneath a fuzzy wax pile that a predator may get a handful of allowing the planthopper to escape,” Kesheimer said.
The fuzz and waxy layer also protects the planthoppers from their own bodily fluids. Due to their piercing-sucking nature, planthoppers intake a lot of plant sap. According to Kesheimer, plant sap is high in sugar but low in nutrients.
In order for the planthoppers to get enough nutrients, they must extract a high volume of plant sap. Their bodies then expel the excess sugar from the sap, creating honeydew.
“As the honeydew hardens and ages, it’s a great place for sooty mold to grow,” Kesheimer said.
Since the planthoppers secrete the honeydew, their waxy coating helps to prevent mold growth and possible death.
Kesheimer says that another striking insect that has a similar make up is the beech blight aphid.
“Also called the boogie woogie aphid, they have protruding white waxy fluffs coming off their rear end,” Kesheimer said. “These aphids also produce copious amounts of honeydew that can lead to sooty mold.”
For more information on planthoppers and beech blight aphids, visit the Alabama Extension website, www.aces.edu.