Periodical Cicadas

Periodical Cicadas: Flying insects of the order Homoptera. While all cicadas have multiple-year life cycles, the varieties that emerge into adulthood all at once are known as periodical cicadas. There are seven species of periodical cicadas in North America, all belonging to the genus Magicicada. Some of these species have 13-year cycles, and others have 17-year cycles. What this means is that each brood spends most of a 13- or 17-year period growing as nymphs in the root systems of their hosts, then emerge en masse as adults to completely overrun their environment.

Like many other insects, adult cicadas are basically breeding machines. All they do during their brief adult lives is gather in crowds, sing a lot and fly around looking for mates. During this time, they feed on plant fluids and make the most alarming racket imaginable.

The dominant theory explaining the brood cycles is that the odd periods allow the cicadas to escape most natural predation. In a single night, millions of cicadas can emerge into tiny areas, and although thousands of them do get eaten, the local predators are usually sated well before they make a dent in the new cicada population.

All cicadas of the same life-cycle emerging in a given year are known collectively as a brood. The North American broods are designated by Roman numerals. Brood XXII emerged in the South in Spring 2001, followed a few months later by Brood VII in New York. Brood XXIII will emerge next year spread throughout the Midwest, followed by Brood VIII in Ohio, Pennsylvania and West Virginia. I like to say this because it sounds nice and ominous, the kind of line the geeky scientist type always says in a disaster movie.

This is the year for the Periodical Cicadas to emerge en masse from their 17 year stint underground as screaming, horny, adult bugs from hell in parts of North America. The "outbreak in 2004 will begin in mid-May, in Maryland and 14 other states, as periodical cicada brood X nymphs emerge."¹ Yes, they are really annoying but they are not really a “plague”.

The best of the good news is they won't be eating mass quanities of plants and pets … in fact they don't eat much during the adult part of their life cycle (the 2 months of noisy torture we will endure). They are not true locusts and this is not a plague of locusts we are anticipating.

Some damage will occur. The females will cut slits in the new growth of deciduous woody plants. She will then lay her eggs in those slits. Those cuts may be numerous enough to kill the growth tips of heavily infested trees and bushes. In established plants it may be like a year when Mother Nature pruned all the new growth. Established trees and bushes will not suffer in the long run from this "natural pruning". Light pruning normally done by the gardener may not even be needed this year.

New and/or small deciduous tree and bush plantings will need protection with a barrier of some sort during May and June. There is no point in using insecticide, it is not only harmful to the environment, it is also futile by virtue of their sheer numbers. The best plan is to just screen the cicadas out with a fine mesh cloth. I will not be planting any new woody plants again until this fall, after the crazed bugs have died off for this cycle. New plantings done in the fall of 2004 can grow unmolested while the eggs and nymphs of the 2021 brood grow underground ... equally unmolested. There will be some eating of roots by nymphs but it isn't ususally deemed enough to be harmful.

While this will not be the year for an outdoor wedding, the damage to established and/or large woody, deciduous plants is temporary. Noise, mess, aggravation yes, damage ... not that much really.

It is also worth noting that evergreens and perennials, annuals and biennials will not be affected beyond being decorated with numerous ornaments of leftover, transparent chitin.

1 http://www.entomology.umd.edu/highlights/cicada.html
http://cic.notlong.com <== "Cicada Emerging From His Shell"