- Facts, Identification & Control
- What does it look like?
- Where does it live?
- What does it eat?
- How does it defend itself?
- What stages of metamorphosis does it go through?
- What special behavior does it exhibit?
- How does this bug affect people?
- Garden News Blog
- Will the Cicadas Hurt Your Plants?
- Some references, if you are interested in this topic
- Cicadas: How to control them
- Size and appearance
- Conservation status
- Other facts
- It’s Cicada Season: Another Year, Another Invasion of Truly Ugly Bugs
- WHAT ARE THE CICADAS DOING?
- WHERE ARE CICADAS APPEARING?
- WHY ARE CICADAS SO DISGUSTING?
- WHEN DO CICADAS GO AWAY AND WHEN WILL THEY COME BACK?
- HOW CAN I FIGHT CICADAS?
- LOOKING FOR MORE INSECT NEWS?
Facts, Identification & Control
What do they look like?
Locust is a common name used incorrectly when identifying cicadas and other families of grasshoppers. The true locusts in the U.S. go by the common name short-horned grasshoppers. Locusts are quite diverse in appearance with more than 600 species found in North America, of which only a few are considered damaging to rangelands, crops and garden plants.
- Size: Typically, locusts are large insects with two antennae that are less than half the length of its body.
- Legs: They have long back legs used for leaping
- Wings: Two wings at both the front and back of the body
- Color: Range in color from very drab to very colorful.
- Head: Locusts have large eyes, heads and chewing mouthparts enabling them to consume large amounts of vegetation.
How Did You Get Locusts?
Locusts are not home invaders and in the adult stage should one venture inside it will not survive long indoors. These insects are not cicadas, but are certain species of grasshoppers usually associated with grasslands, so their feeding habits may lure them to agricultural crop fields, gardens, mature plants and seedlings in lawns. While a locust may accidently get inside through a door or window, these pests do not infest homes and can be easily removed by using a paper towel or napkin to grab and dispose of the locust in the trash.
How Serious Are Locusts?
Locusts rarely, if ever bite people. However, because of their diet, the pests do damage growing plants and vegetables. A large locust population can wipe out a garden in a short time. In addition, due to their behavior, agility and sometimes huge populations, these insects are difficult to exclude from ornamentals and other plants. These insects are also commonly called migratory grasshoppers and the damage they’ve created in the past is legendary as they migrate from one location to another, sometimes consuming all of the plant matter they come across.
How Do You Get Rid of Locusts?
How Orkin treats for locusts
The true locusts in the U.S. go by the common name short-horned grasshoppers and are not the same insects as cicadas.
North America is home to over six hundred different species of locusts. Most of which are diverse in appearance, and only a few species damage rangelands, crops, and gardens. Therefore, before attempting a treatment program for locusts, always contact your pest management professional.
Locust treatment can be very challenging since their behavior involves adults flying into an area, feeding on vegetation and then moving onto another feeding location.
Localized treatment of heavy locust infestations generally consists of using chemical sprays applied directly to plants or the locusts, themselves. Selecting the proper chemical insecticides depends on whether the product’s label allows application to fruits or vegetables. If chemical products are used, selecting a product is best left to your pest management professional.
There are some effective non-chemical methods that your pest management professional may recommend for the treatment program. These might include:
- Protecting valuable shrubs and garden plants with insect mesh or cloth that is not green because green colors tend to attract locusts.
- Removing locusts by handpicking them off plants.
- Leaving areas of tall, uncut grass so locusts have alternative food sources and harborage sites that provide other plants to feed on and reduce the likelihood of damage to landscaping or garden plants.
Behavior, Diet & Habits
Where do they live?
Most locust species are found in grasslands; however some may be seen in forested or aquatic environments.
Reproduction & Life Cycle
The life cycle consists of egg, nymph (wingless state) and winged adults and is typically completed in one year. Mating between males and females may take up to an hour. Some locust species participate in a behavior known as mate guarding, whereby the male rides on back of the female for a period of a day or more. Females typically deposit their eggs in the ground in an egg cluster of 8-25 eggs. Eggs are normally laid in the late summer, and overwinter before hatching in the spring.
The notorious, ravenous, swarming, migratory locusts common in areas of Africa and elsewhere in the “Old World” have been around since ancient times and still cause extensive destruction to crops and grasslands where they are found. The Rocky Mountain locust (Melanoplus spretus), thought by many to now be extinct in the U.S., had a behavior and swarm numbers similar to the “Old World” locusts and caused monumental losses to agriculture and plains states’ pastures in the 1800s. While it may seem repulsive to most people, locusts are considered a delicacy in some parts of the world.
What does it look like?
Cicadas are large insects between 1 and 2-3/8 inches long. Most are black with greenish markings. They have a stout body, a broad head, and short antennae. Their large compound eyes are set wide apart. Three small eyes (ocelli) are arranged in a triangle. Clear wings with sturdy veins are attached to the thorax. Wings are held roof-like over the abdomen. There are six legs with strong claws for gripping bark. Immature cicadas look like adults, but have tiny wings or no wings at all. Males have sound-producing organs below the base of the abdomen. Cicadas are sometimes called locusts but do not jump like locusts.
Periodical cicadas are 3/4 to 1-1/4 inches long. They are black-to-brownish in color with reddish-brown to yellow under the abdomen. Wings have an orange tinge; legs are reddish. Front wings are twice as long as back wings. Wingspan can be up to 3 inches. One Chinese species is 7 inches long with an 8-inch wing span!
Some cicada species are colorful. Magicicadas have black bodies, red eyes, and wings with orange veins. Near the tip of each forewing is a black “W”. The species Okanagana is colored black and orange. “Stop-and-go” cicadas of Ecuador have wings with red and green markings. Some cicada species are odd looking. The male bladder cicada of Australia has a large, balloon-like abdomen.
Scientists identify cicada species by their sounds or “songs”. Male cicadas have 2 thin membranes (tymbals) on the sides of the abdomen. Muscles pull the tymbals inward to make a clicking sound. When muscles relax, the tymbals snap back to make a different sound. This happens 300 times per second! The hollow abdomen amplifies the sound like a drum.
Where does it live?
Periodical cicada species (Magicicada) are found east of the Mississippi River from the Great Lakes to the Gulf of Mexico. Their habitat is deciduous mixed forests and nearby grasslands and pastures.
Unlike other cicadas, periodical cicadas emerge only once every 13 or 17 years. When they all emerge at one time they are called a “brood”. Some broods are large while others are small. There are only 14 broods of 17-year cicadas and 5 broods of 13-year cicadas in the United States. The 17-year species are mostly in northern regions. The 13-year species are generally in southern and midwestern regions.
What does it eat?
Cicadas belong to the insect order Homoptera because they have sucking mouthparts. Insects in this order pierce a root or stem then suck up the fluid from plants. Periodical cicadas feed on the sap of tree roots to get food. This is how they stay cool in the summer and keep from drying out.
How does it defend itself?
Insect-eating birds and various animals eat cicadas. Male cicadas use vibrating membranes on the abdomen to warn of danger. Cicadas can fly away from predators. They are fast fliers, but sometimes bump into trees and other objects. Enemies are usually overwhelmed by the sheer number of emerging cicadas. Predators eat their fill and many cicadas remain.
What stages of metamorphosis does it go through?
Cicadas undergo simple or incomplete metamorphosis. There are three stages of development— egg, nymph, and adult. To lay eggs, females use an ovipositor to make a slit in a twig. The twig dies and falls to the ground where eggs are left. Sometimes young cicada nymphs hatch from eggs and drop to the ground without the twig. Upon reaching the ground, they use strong front legs to dig underground burrows in the soil where they will live.
Cicadas molt through several nymph stages before emerging as adults. There are no larva or pupa stages. When the soil gets warm enough in spring (about 64 degrees F), nymphs dig exit tunnels to find air. They climb a tree to undergo one last molt. When the exoskeleton splits down the back, the adult wriggles out.
Newly emerged adults are milky white. In 2 or 3 hours their bodies turn black. The wings are thick little flaps. Fluid pumps through a network of veins to expand the wings. The wing veins turn bright orange and eyes turn bright red. When wings unfold and dry out, cicadas crawl or fly up to the treetops.
Most cicada species have lifecycles between 2 and 8 years. These species are often called “annual” cicadas. Annual broods overlap so adults can be found every year. Species in each lifecycle group have different sizes, colors, and songs. In contrast, “periodical” cicadas mature together in long lifecycles of 13 or 17 years. Periodical cicadas have a 3-stage lifecycle too, but spend many years as nymphs. Most of the emerging periodical cicada broods contain 2 or 3 species.
Annual species appear every year in midsummer. Thousands of empty nymph skins can be seen hanging from trees during July and August. They are called “dog day” cicadas. Ancient people believed the sun’s heat combined with heat from Sirius the Dog Star. They called the hot days of mid-summer “dog days”.
The lifecycle of periodical cicadas is between 13 and 17 years. They appear in May and June. Periodical cicada adults are present in a given area only in certain years. Most of their time is spent underground in the nymph stage.
What special behavior does it exhibit?
The word cicada means “buzzer” in Latin. Each cicada species has a distinctive song, such as a loud buzz or hum. Every song varies in tone and rhythm. Some species are more “musical” than others. Sometimes they make a clicking or whining sound. When thousands sing at the same time they are very loud.
Male cicadas make sounds using tymbals–special structures found on the abdomen. Male cicadas make sounds to lure females. Males begin making their sounds a few days after emerging from underground. They often stay close together in “chorusing centers” that attract females. They stop singing in the evening.
Periodical cicada nymphs are able to burrow as deep as 8 feet to find roots where they can feed. They are able to tell when thirteen or seventeen years have passed by tasting juices sucked from the roots. These fluids change as trees grow through the seasons. If the cicadas count wrong they will not emerge at the right time.
When they hatch, millions of cicadas suddenly appear as if by magic from soil. They have the scientific name Magicicada. The different broods of Magicicada in the United States usually emerge as adults on separate schedules. Every 221 years they come out together!
How does this bug affect people?
Cicadas have fascinated people since ancient times. They are well liked by people in most countries of the world. In France they are thought to bring good luck. They are a source of food for people in Africa, Asia, and Latin America. In ancient China they were a symbol of rebirth.
In 1634, Pilgrims in New England heard a population of cicadas known as Brood XIV. This population lives in parts of 13 states including Massachusetts where Pilgrims first settled. The Pilgrims thought cicadas were plague locusts like those in Bible stories. Brood XIV last appeared in 2008. The next generation will appear in 2025.
Cicadas cannot bite or sting. They have no economic value. Sometimes, when large populations crowd into a small area, damage can occur. Too many cicadas feeding and laying eggs can harm young trees. Older trees usually escape with little damage.
Leahy, C. (1987). Peterson’s first guide to insects of North America. Boston, MA: Houghton Mifflin Company.
Pringle, L. (2010). Cicadas! Strange and Wonderful. Honesdale, PA: Boyd Mills Press.
Cicadas often are incorrectly called locusts. In fact, locust is the common name for the group of insects that are categorized as short-horned grasshoppers.
What Do They Look Like?
- Length: Adult cicadas vary in size depending upon the particular species, but are generally about 2-3 inches long.
- Wings: They have large, clear wings with many easily seen wing veins. The cicada’s immature stage, called the nymph, is wingless.
- Eyes: Their eyes are large, reddish or black and set apart on each side of the head.
Annual vs. Periodical
There are two basic groups of cicadas: annual vs. periodical. Most species of cicadas in the U.S. are annual cicadas, meaning cicada season occurs every year.
While annual cicadas complete their life cycle and emerge from the soil habitat every year, Periodical cicadas emerge at either a 13 or 17-year interval. Periodical cicadas are so predictable that charts are created to forecast when and in what states they will appear.
How Did I Get Cicadas?
Where Do They Live?
Different species of cicadas emerge in large numbers during the summer. The pests develop in the soil and hang out on plants or trees. People might find shed cicada skins littered on and around tree trunks and yards.
Do They Infest Homes?
These insects are strong but clumsy fliers, sometimes running into objects that get in their way. It is common for a cicada to fly into a home, especially when residents leave doors or windows open. Cicadas cannot breed indoors, so infestations in houses are unlikely.
How Serious Are Cicadas?
Cicadas do not eat leaves, but may harm some plants when they lay eggs. Typically, homeowners only have problems with cast-off cicada skins, which pile up in yards and on patios. The pests do not carry diseases and do not bite or sting people. Most issues with cicadas relate to their noisy and messy behaviors.
Males make loud, shrill calls that some residents find annoying. Cicada “singing” can be heard for up to 1/2 mile away, making cicadas the loudest of any other insect in the U.S.
How Do I Get Rid of Cicadas?
What Orkin Does
The first step in a cicada treatment program is to understand the behavior of the pest cicadas and to know whether the insect is an annual or periodical cicada. Your pest management professional will conduct an inspection and, based on his or her findings, will prepare the cicada treatment plan.
Chemical treatments generally are not required for use on homeowner properties. Since cicadas complete their nymphal stage in the ground, emerge and become adults who live for only about 2-4 weeks, soil treatment with chemicals is usually not worthwhile unless cicadas are active in a commercial orchard or ornamental plant nursery.
Additionally, chemical treatments have little to no effect on “migrating populations,” as the pests often move to one’s property from adjacent, untreated and infested locations.
Protecting Plants: What You Can Do
Avoid using insecticides since cicadas will come to your plants from locations outside your property in such large numbers that spraying is of little benefit. Some effective non-chemical methods of cicada treatment include:
- By Hand – Picking adults and nymphs off plants by hand, if found in small enough numbers.
- Garden Hose – Knocking cicadas off plants by spraying water with a garden hose.
- Foil & Barrier Tape – Wrapping tree trunks and large bushes with foil or sticky bands (barrier tape) to catch cicadas trying to move up plants to feed or lay eggs.
- Netting – Protecting young or valuable plants by covering them with netting.
The female adult cicada lays eggs on trees and shrubs by inserting the eggs into the small twigs at the outer end of branches. Eggs hatch in about 40-60 days and become nymphs.
Nymphs drop to the ground, burrow about 1 – 2 feet into the soil where they feed on the fluids in the small roots of the host plant. Mature nymphs emerge from the soil, climb onto surrounding trees or shrubs and mature into adults. Soil temperatures of 64 degrees trigger emergence of the nymphs.
Adults live for about 14-50 days during which time they mate, lay eggs, and die.
One of the most impressive cicada predators is the cicada killer wasp, a burrowing insect that looks like a huge yellow jacket. During the time of year that adult cicadas are active, cicada killer wasps are often seen either carrying or burying a cicada that was paralyzed by the wasp’s sting.
More About Cicadas
Garden News Blog
Will the Cicadas Hurt Your Plants?
By Melanie Sifton | May 7, 2013
You’ve no doubt heard about the large brood of 17-year cicadas that will soon emerge in New York City and beyond. If you garden, you’ve probably wondered what these gigantic insects might do to your plants. The good news is that adult cicadas (Magicicada species), though large and noisy, do not tend to do much damage. The primary reason for their emergence is to mate! That deafening song is a mating call. Eating plants is probably one of the last things on a cicada’s mind.
Cicada grubs do eat plant roots and are a common underground pest, but they’re not too serious, and any harm that this brood has done was done in previous years. The only damage adult cicadas are likely to cause plants, even during a heavy emergence, is from ovipositing. The females cut small V-shaped slits into tree bark or plant stems to deposit their eggs. This can cause branches or stems to flag, but it’s generally not a major concern for healthy plants and trees.
Cicadas can’t bite or sting people, and they are not poisonous. They are mostly pesky only because of their loud singing, imposing presence, and conspicuous numbers. Please do not think about using pesticides on them. It’s unnecessary and not at all justified.
More: Cicadas are considered true bugs, but ants and bees aren’t. Learn why.
Overall, the emergence of the 17-year cicadas should be an amazing phenomenon to observe. They are quite beautiful in their own right, and their song is among the loudest in the insect world. They are also one of the longest-lived insects on earth and are a symbol of good fortune and immortality in various cultures around the world. So instead of likening cicadas to a plague of locusts, try to enjoy their short visit and appreciate them in all their noisy glory. You can check out Radiolab’s citizen science–produced cicada-prediction map and read more about this Magicicada brood online at EarthSky.org.
Melanie Sifton is the vice president of Horticulture and Facilities at Brooklyn Botanic Garden.
The primary focus of this article is 17 and 13 year cicadas (Magicicada). Most other cicadas are nothing to worry about, with some exceptions1.
People ask: “Will the cicadas kill my trees, shrubs or flowers?” The short answer is “maybe”, particularly if your trees are pathetic weaklings. Here are some ways to defend your trees, other than chemical warfare.
Read on for more information:
First, it is important to mention that cicadas do not cause damage to plants by chewing leaves like other insects do, such as caterpillars. These are not the locusts associated with destroying the entire food supply of nations, nor are they the locusts mentioned in the Bible.
Damage from cicadas occurs during ovipositing, or in some extreme cases, when they feed on the roots of trees4.
Grooves made by a cicada during ovipositing:
The weakest limbs of a tree are often temporarily damaged or killed off, the result of which is called flagging, as the leaves of the branch will turn brown and look like a hanging flag. In many cases, they are doing the trees a favor by pruning their weakest branches.
An image of Flagging caused by cicadas:
Cicadas are technically parasites of the trees, and they need the trees to survive throughout their life cycle, so killing trees is not in the cicadas best interest. If cicadas were tree killers, there would be no trees, and no cicadas left.
Big, Hearty North American Trees:
Deciduous trees, like elm, chestnut, ash, maple, and oak, are the preferred host trees of periodical cicadas. They will flag the branches of these trees, but only young ones are at risk.
Don’t believe me? Read this quote from the paper Periodical Cicada (Magicicada cassini) Oviposition Damage: Visually Impressive yet Dynamically Irrelevant by William M. Hook and Robert D. Holt (Am. Midl. Nat. 147:214-224).
The widespread oviposition damage from periodical cicadas did not have any important effects on successional dynamics of the host plants, suggesting that the trees appeared to compensate sufficiently for physiological damage during the emergence.
Periodical cicadas avoid evergreen trees for egg laying because the sap interferes with their egg nests.
Fruit trees: Farmers expect every branch of their fruit trees to yield fruit. They will not tolerate ovipositing & flagging by cicadas.
The smaller species of Magicicada, ‘cassini & ‘decula, like ovipositing on trees on the edge of a forest, probably because their offspring will be more likely to find grass roots when they leave their egg nests (cicadas initially feed on grass roots until they are big enough to reach and feed on the larger rootlets of trees). An orchard is all “edge of a forest” because of the rows between the trees, so it ends up being what the legal system would call an “attractive nuisance” for cicadas, because the farmers are baiting the cicadas by providing the ideal egg-laying environment, only to kill them with pesticides.
Another consideration is that many fruiting trees are not native to North America. Apples, for instance, are from Asia and are not prepared/evolved for the egg-laying behaviors of cicadas.
Small or Ornamental Trees: Cicadas pose the largest threat to small, weakling, ornamental trees, and young deciduous trees. These trees will have the fewest branches, and will not be able to suffer a heavy loss. These are the trees you can worry about, but there are ways to defend them. It makes sense to avoid planting ornamental, fruit or or other deciduous trees the year before and of a cicada emergence — make it the year you concentrate on pavers and low, ground-covering plants like vines and pachysandra.
Shrubs, Vegetables, & Flowers: Given a choice, cicadas will avoid ovipositing on shrubs and long stem flowers, but if the emergence is particularly heavy, they’ll give it a try, out of desperation.
Small flowers, like marigolds, pansies and zinnia will have the best chance of avoiding cicada egg-laying behavior since their stems are so short and unappealing for egg laying.
I’ve experienced the full duration of two emergences of Brood II. During neither event did I witness the loss of a small tree, shrub or flowering plant. I saw a dogwood tree withstand two emergences, although it did experience ovipositing on nearly every stem, and it lost multiple branches due to flagging. In 1996, our small ornamental red maple withstood the cicada emergence without memorable issues (that plant was lost to a fungal blight many years later). I cannot remember any damage to scrubs such as boxwoods and forsythia, or garden flowers. Your personal experience might be different.
And of course: Good Luck!
Some references, if you are interested in this topic
1 Certain cicada species in Australia will damage sugar cane and grape vines, but not in North America.
3 Spatial variability in oviposition damage by periodical cicadas in a fragmented landscape by William M. Cook, Robert D. Holt & Jin Yao. Oecologia (2001) 127:51–61.
4 Periodical Cicadas in 1963, Brood 23 by D.W. Hamilton & M.L. Cleveland. 1964. Proc. Indiana Acad. Sci. for 1963, 72; 167-170.
Cicadas: How to control them
2 Types of Cicada Damage
Cicadas harm your plants in two ways. They can feed on the roots of your plants, but most of the damage is done when the females lay their eggs in your trees. Females have a sawlike egg-laying organ that they use to cut through the bark and the sapwood of twigs. They then lay up to twenty rows of eggs that number from 24 to 48 per row. Female cicadas prefer to lay their eggs in ¼- to ½-inch diameter branches of oak, maple, hawthorn, redbud, fruit (especially cherry and pear), and any young trees.
A Peculiar Lifestyle
After hatching, cicadas will burrow themselves in the soil where they live for long periods of time before reappearing above ground. The periodical cicada has a southern race, which has a 13-year life cycle, and a northern race, which lives for 17 years underground. Fortunately, they have a consistent life cycle, making time of appearance easy to predict. The annual, or dog day, cicada spends 2-5 years in the ground before hatching in July and August.
Muffle Their Noises
Although there’s not much you can do to prevent a brood from emerging, you can control how much damage they do to your yard. If you are in a region where a periodical cicada brood is expected, do not plant young trees until fall and cover young trees, especially those planted that spring, with mosquito netting. Remove damaged, brown twigs as soon as you see them. Adult cicadas can be controlled by using Ortho® Home Defense® Insect Killer for Lawn & Landscape.
Jane Stevens, an entomologist at the St. Louis Zoo, offers the following answer.
Image: Roy Troutman
MAGICICADA. Most sap-sucking cicadas appear periodically, every 13 or 17 years. There are both 13-year and 17-year species of the Magicicada shown.
The 13-year and 17-year cicadas, known as periodical cicadas, are both large-bodied insects with orange-veined wings. And this summer, the raucous buzzing heard around St. Louis comes from both varieties–the first such occurrence in 221 years.
Despite their fearsome appearance, with bulging, bright red eyes, these members of the Homoptera order of insects (other members being leafhoppers and aphids) are harmless to animal life and all trees but young saplings. The daytime noisemakers are indefatigable in calling for a mate. The din from large broods readily overwhelms competition from even the noisiest lawnmower.
Periodical cicadas occur in three pairs of species–each pair comprised of a 17-year and a 13-year species. (There are other cicadas, such as dog-day cicadas, which have only a four-year life cycle.) The periodical varieties look, sound and behave alike. The only characteristic distinguishing them from one another is the length of time they spend in the ground during the nymphal stages–either 13 or 17 years.
After cicada eggs hatch, the antlike nymphs quickly drop from the trees and burrow five to 46 centimeters (two to 18 inches) underground in search of tree roots to feed upon. After 13 or 17 years, a natural “clock,” which remains a mystery to scientists, indicates that it is time to surface; the nymphs leave the ground, abandon their brown and brittle exoskeletons and ascend to the treetops to begin their constant buzzing calls. Mating occurs, eggs are laid and the cycle begins again.
Image: Roy Troutman
MOLTING. After the nymphal stage spent underground, cicadas shed their exoskeleton and climb nearby trees to mate.
Scientists identify groups of cicada species that emerge at the same time and in the same place by an assigned brood number. Brood maps show where specific groups of cicadas will emerge, and brood lists estimate the years during which they will appear.
Periodical cicadas have several distinguishable calls: calls to attract males to make the all-male chorus larger and louder, which in turn attracts more of the silent but interested females; courting calls; and the alarm call, that loud buzzing you hear when you pick one up.
After mating, adult female cicadas use their blade like ovipositor to make elongated openings in new growth sections of tree branches. A female usually lays 20 to 30 eggs in each opening, and there can be several egg “nests” per branch. During her brief adult life stage, each female lays approximately 600 eggs. The eggs take six to eight weeks to mature–after which the nymphs drop to the ground and immediately begin their descent into an underground habitat. Their lengthy nymphal stage is unparalleled within the animal kingdom and continues to draw the interest of scientists.
For an insect aficionado, it’s been a great summer to live in Missouri: a rare emergence of both of the largest broods of 17-year and 13-year cicadas–Broods IV and XIX, respectively–is occurring here for the first time in 221 years. Brood XIX has emerged in the eastern and central parts of the state and Brood IV in northwestern areas. There are, however, a few small places in central Missouri where the two species overlap.
Rest assured, the loud noise and those who make it are on a tight schedule. Their stay, this time around, is almost up.
Cicadas are oval-shaped, winged insects that provide a buzzing and clicking song heard in nature throughout the summer. Most cicadas appear every year in late June through August, while others emerge only every few years.
Size and appearance
There are around 3,000 cicada species, according to National Geographic, so they vary in size from 0.75 to 2.25 in (2.2 to 5.5 cm) long. Cicadas can be black, brown or green and can have red, white or blue eyes.
Their wings are transparent and can seem rainbow-hued when held up to a light source. The veins on the tips of the wings of some cicadas make the shape of a W.
Cicadas are found only in the eastern half of the United States. They live a relatively long time — 4 to 17 years, depending on whether they are annual or periodical cicadas. The periodical cicadas live the longest.
They spend most of their lives underground as larvae, followed by a short adulthood — from two to six weeks — above ground, according to the University of Michigan’s Museum of Zoology.
There are generally two types of cicadas. Annual cicadas emerge every year in late June or August, while periodical cicadas emerge in cycles of 13 or 17 years, depending on the species. When periodical cicadas emerge, all the adults in a given location emerge at the same. Tens of thousands to over a million insects can reside in a relatively small area of land. A group of periodicals that emerge at the same time is called a brood. Broods are classified with Roman numerals that represent each group. There are 30 broods in all.
Though a group of these insects are called a cloud or plague, cicadas usually don’t cause the harm that locusts cause to crops and local vegetation.
Cicadas are herbivores. This means they eat vegetation. Young cicadas eat liquid from plant roots, while molting cicadas eat twigs. Adult cicadas do not feed, according to U.S. Department of Agriculture.
Cicada nymphs emerge after a 17-year childhood underground. Over the course of just a few weeks, they molt, mate, and die. Their babies will hatch in trees and find their way back to the dirt to continue the strange cycle. (Image credit: Julie Larsen Maher/WCS )
The buzzing sound they make is a mating call. Male cicadas vibrate a white, drumlike membrane on their abdomens called a tymbal. A group of singing cicadas is called a chorus. The singing attracts both males and females to a certain area. The males join in on the singing and the females mate with the males.
Cicadas start their lives as eggs above ground. When they hatch, they burrow down into the ground. For food, they suck liquid out of plant roots, since their mothers do not care for them. The babies, known as nymphs, molt in five growth cycles. These growth cycles are called instars.
It is thought that cicadas know when to all emerge at once due to ground temperature. When the ground temperature at a depth of 8 inches (20 centimeters) reaches 64 degrees Fahrenheit (18 degrees Celsius) the nymphs know it is time to come out, according to the National Oceanic and Atmospheric Administration. Some think that other factors, such as changes in tree’s root fluid, may also signal nymphs to emerge.
Once top-side, the nymphs grow wings and appear white. As their exoskeleton hardens they become darker. The hardening can take four to six days, according to the University of Michigan. Once they are fully hardened, they are mature and ready to mate. The females lay around 20 eggs at a time in slits they cut in tree branches. The eggs hatch within six to 10 weeks.
Here is the taxonomy of cicadas, according to the Integrated Taxonomic Information System:
Kingdom: Animalia Subkingdom: Bilateria Infrakingdom: Protostomia Superphylum: Ecdysozoa Phylum: Arthropoda Subphylum: Hexapoda Class: Insecta Subclass: Pterygota Infraclass: Neoptera Superorder: Paraneoptera Order: Hemiptera Suborder: Auchenorrhyncha Infraorder: Cicadomorpha Superfamily: Cicadoidea Family: Cicadidae
The most prominent and best-studied cicadas are six periodical species belonging to the genus Magicicada, according to the University of Michigan. Three species have 13-year cycles, and three have 17-year cycles.
An adult Cicada emerges from its juvenile exoskeleton in the Peruvian Amazon (Image credit: Ryan M. Bolton )
While no species of cicada are endangered, a few are at risk, according to the International Union for Conservation of Nature (IUCN). The union’s Red List of Threatened Species lists the Cassini periodical cicada, the Decim periodical cicada and the Decula periodical cicada as lower risk/near threatened, although no reasons for those assessment are given.
Some cicada calls can be heard up to 1 mile (1.5 kilometer) away, according to National Geographic.
Cicadas do not sting or bite, according to the University of Michigan.
When they leave their burrow, sometimes cicadas will make chimneys of mud over the exit.
Each species of cicada has a different song.
- National Geographic: Cicada Recipes- Bugs Are Low-Carb, Gluten-Free Food
- Vanderbilt University: Bad buzz about blue-eyed cicadas
- RadioLab: Cicada Tracker
Cicadaville appeared online on May 5, the invention of Brandon Breedon, a writer for derfmagazine.com, a satirical Web magazine based in Cincinnati. He and his colleagues at Derfmagazine, Mr. Breedon said, figured that ”we’ll do our part to put misinformation out there.”
There are other cicadavilles, as well, some of which peddle cicadawear. At cafeshops.com/cicadaville, you can get a shirt that says ”Cicada Go Crunch” or ”Resistance Is Futile. Join Brood X” or a thong with the internationally recognized no-cicada symbol. I don’t see how anyone could argue with the sentiment expressed on the thong. I certainly wouldn’t want cicadas in my underwear, even if they don’t bite.
Real locusts do bite, and not just plants. Dr. Lockwood writes, ”We expect grasshoppers and locusts to consume our gardens and fields, but when these insects begin to feed on fabric and flesh, something seems demonically amiss.”
They ate the clothes off settlers trying to fight them. They ate dead bats and birds. They ate other locusts that humans had killed or maimed. Dr. Lockwood quotes from Gen. Alfred Sully, who describes a soldier’s sleeping on the prairie at midday after a night’s march between the Missouri and Yellowstone Rivers in the summer of 1864. The general wrote: ”His companions noticed him covered with grasshoppers and awakened him. His throat and wrists were bleeding from the bites of the insects.”
The largest locust swarm on record, Dr. Lockwood reports, was documented from June 15 to 25, 1875, in Nebraska. Albert Child, who observed it and made a careful analysis, calculated that the swarm covered 198,000 square miles and was a quarter- to a half-mile deep. Dr. Lockwood says the damage supports that claim, and he estimates the number of locusts at 3.5 trillion. Nationwide, at the peak of a major outbreak, he estimated that there were 15 trillion locusts with a biomass approaching that of bison at their peak.
It’s Cicada Season: Another Year, Another Invasion of Truly Ugly Bugs
The arrival of a cicada swarm is often compared to a Biblical plague. Seemingly overnight, an area can be overwhelmed with thousands, if not millions, of flying bugs that seem to be everywhere.
But unlike Biblical plagues, cicada swarms do little damage to the environment when they reach adulthood. Instead, these insects are most well-known for an intense, loud mating call … and for scaring people with their creepy appearance.
WHAT ARE THE CICADAS DOING?
When cicadas emerge from the ground, they have only one thing on their mind – mating. Male cicadas settle down on tree branches where they emit an ear-splitting noise meant to impress female cicadas. In some species, this mating call can reach 120 decibels, which is about as loud as an in-use chainsaw. North American cicadas seem to max out around 110 decibels, which is comparable to a steel mill in full operation. Despite this ear-splitting noise, humans often find it difficult to determine the direction of a cicada call.
The male will die shortly after mating. The female, however, lives on to lay her eggs. In most species found in North America, the female cicada cuts a slit through tree bark and then lays her eggs inside. Once she completes this task in several locations, she too dies.
Their offspring hatch shortly thereafter, drop to the ground and bury themselves, where they can remain underground for years.
WHERE ARE CICADAS APPEARING?
In general, some cicadas appear yearly in every region of the United States. Massive outbreaks, however, develop at the end of certain broods’ periodic cycles and those outbreaks are regional in nature.
In 2016, the periodic group called Brood V is emerging in Maryland, Ohio, Pennsylvania, Virginia and West Virginia. The following year, 2017, will hail the arrival of Brood VI in Georgia, North Carolina, and South Carolina. New York will see the big outbreak of Brood VII in 2018. Another group, Brood VIII, hits Ohio, Pennsylvania, and West Virginia in 2019.
Like most insects, cicadas seem to prefer specific types of plants to roost upon and lay their eggs. Cicadas in North America are attracted to these plants:
- Black-eyed Susan
- Fruit trees and berry bushes of all kinds
- Japanese Maple
- Rose of Sharon
These plants, if young or weakened by disease, can be damaged by cicadas, but most weather the cicada swarms. However, certain parts of these plants may experience a condition called flagging, when the leaves at the tips of host branches turn brown.
WHY ARE CICADAS SO DISGUSTING?
When it comes to appearance, cicadas are the stuff of nightmares. These large housefly-shaped insects have a sickly, caramel-colored exoskeleton and transparent wings with veins sprouting from their thorax. Their foremost pair of legs is especially long, which helps them cling to tree limbs. Hidden on their underside is a long tube protruding from their head, which they stab into plants in an effort to suck out the plant’s nourishing juices – their only food source during adulthood. To top off that interesting collection of body parts, most cicadas have red eyes – not red-tinted eyes either – their eyes are literally fire engine red! In fact, it’s easy to confuse a cicada for a June bug, since they appear around the same time and both are about the same size. That being said, cicadas are definitely a lot uglier.
Beyond their horrid appearance, lots of dead cicadas can create a foul stench. In areas where there’s been a major emergence of these insects, the millions of cicadas all die around the same time and then fall to the ground. As their bodies begin to rot, the smell gets worse. If you see this happening in your yard, it’s a good idea to rake up the corpses and bury them in a hole. Composting them is another option.
About a month and a half to two months after the big die-off, the next generation of cicadas hatches. These cicada nymphs, usually white in color and about ¼ of an inch long, quickly go underground.
WHEN DO CICADAS GO AWAY AND WHEN WILL THEY COME BACK?
Scientists believe that, on emergent years, cicada nymphs leave the soil when temperatures reach 65° F about 8 inches below the surface. After finding a tree to rest in, they molt one last time and emerge as adults. At this point, adults live about four to six more weeks before dying off.
The amazing part about periodic cicadas is that some species will stay underground for 13 years and others will stay underground for 17 years. Scientists find it interesting that both these periods are prime numbers and suspect that there is some biological molecular clock that counts off the years for these insects. In a sense, that’s good news — if you have a major cicada outbreak this year you won’t have to worry about another outbreak for more than a decade!
Why are their emergent years set so far apart? Again, scientists have a theory – they believe it’s to keep predators from relying on these fat bugs as a food source.
Of course, not all cicadas have such a well-tuned biological wristwatch – some will emerge from the soil in the wrong year for their particular species or brood.
Other species, as we mentioned above, emerge from the soil on a more regular basis. These cicadas are usually parts of broods that are on cycles as short as once every two years. These smaller broods are so indistinguishable that many people assume they are on an annual cycle.
HOW CAN I FIGHT CICADAS?
One of the best ways you can battle cicadas is by enticing cicada killer wasps into your yard. These wasps, which don’t normally sting people, are on the large side – measuring about 2 inches long. Of course, not many people are eager to have two-inch-long wasps in their yard either!
Birds and other wildlife are also opportunistic cicada predators. What cicadas lack in good looks, they apparently make up for in good eating! As with any large insect, cicadas offer a protein boost to anyone willing to eat one. Even humans will eat cicadas – there are plenty of recipes available online!
Beyond finding predators to eat your cicadas, it’s probably easiest to wait them out. With their short, above-the-ground lifespan, cicadas are a minor annoyance at best.
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