Bad news for folks that were looking forward to some peaceful summer evenings hanging out on the porch. Billions of cicadas will soon be emerging from a 17-year stint underground, filling the skies and trees and quiet nights across a sizeable chunk of the U.S. Michael Schauff of the Agricultural Research Service says the cicada explosion this year will start in early-to-mid May, with activity peaking between mid-May and mid-June. Some folks could see them emerge as soon as April, depending on the latitude and weather.
When soils reach 64 degrees Fahrenheit, hundreds of millions of cicada nymphs will simultaneously burrow their way to the surface and make their mass emergence after living underground for the past 17 years. According to Schauff, the first sign of the cicada emergence will be little mounds or mud turrets that look like miniature volcanoes around the bases of trees. The insects emerge soon after.
Once the cicadas are above ground, they will climb on the nearest thing they can find to molt one final time as they prepare to begin looking for a mate. And that’s when things get loud. Depending on how concentrated they are in an area, the humming and whirring mating calls that are made by the males can be downright deafening. After mating, the females lay hundreds of eggs on tree branches. When those hatch, the new nymphs fall from the trees and burrow under the ground. Meanwhile, all the adults just die off four to six weeks after emerging. Why they do this in cycles of 17 years (13 years for some) is one of the biggest mysteries in nature.
Though as many as 1.5 million cicadas may crowd into a single acre, unlike locusts, cicadas don’t eat vegetation so they do not pose the same risks to crops, although small or newly planted hardwood or fruit trees and grapevines may need protection. Cicadas drink the sap from tree roots, twigs, and branches. Many folks who experienced large cicada populations in 2011 were left with damaged young trees and bushes where the female cicadas cut slits into tree branches to lay their eggs. The cicadas prefer stems and branches about the diameter of a pencil to deposit their eggs; on mature trees only the branch tips are damaged and the trees recover. Early American colonists first encountered periodical cicadas in Massachusetts. The sudden appearance of so many insects reminded them of biblical plagues of locusts, which are a type of grasshopper. That’s how the name “locust” became incorrectly associated with cicadas in North America. (Sources: National Geographic, USDA, CicadaMania)