We are preparing for the onslaught of the 17-year cicada. The East Coast is supposedly going to get hit hard. I am concerned about my newly planted cherry trees. Is it possible that I might lose them? What (if anything) can I do to protect them?
Because of the unusual life cycle of the 17-year cicada we tend to think of their emergence from dormancy in biblical proportions. And considering that a single female can produce 400 to 600 offspring, this correlation is not too far off.
There are two types of cicadas that you may be familiar with, periodical cicadas and annual cicadas. Periodical cicadas include 17-year and 13-year species. They are black, sometimes with gold banding and have red eyes. Annual or "dog day" cicadas are green, appear every year in late summer and are generally harmless. And while a swarm of loud, large flying insects with bulging red eyes sounds terrifying, periodical cicadas are also quite harmless to people and most plants.
Every 17 years a biological alarm sounds awakening cicada nymphs from dormancy. They emerge from the ground, climb and attach themselves to nearby trees where they shed their shells or exoskeletons. They will remain on the tree for about 24 hours until their bodies and wings have time to harden.
After about 5 days the males will begin "singing" to attract females for mating. The fertilized female will then lay eggs in the small branches of trees and this is when the trouble starts. The female cicada will puncture the bark in a thin line in which to deposit her eggs. She will sometimes do this as many as a dozen times on a branch. This stops the flow of nutrients through the bark and woody tissue to ends of the branch. Mature trees are not in much danger, but this can be very damaging to young saplings with thin limbs. And cicadas have favorite trees, which include oaks, redbuds, hawthorns, maples, dogwoods, fruit trees and crabapples. Evergreens seem to escape their attention.
After about 6 weeks the eggs will hatch and the newest generation of cicadas will dig down into the ground where they will remain for another 17 years, feeding off of tree roots.
The whole process takes about 2 months and there is not much you can do about it but batten down the hatches and wait it out. You can cover your young trees and shrubs with a lightweight cloth that has openings less than 1/2-inch. Some people recommend cheesecloth. Also, wait to do any planting in your garden until after the cicadas have completed their mating cycle.
This really will be an interesting event that I am quite excited about. After all we haven’t seen the cicada since 1987 and won’t see it again until 2021.