Many periodical cicadas emerged four years early in the Chicago area in 2020. These cicadas belong to the Brood XIII (13) which is set to emerge in 2024, and last emerged in 2007. Periodical cicadas often emerge in years proceeding or following the year their brood is expected to emerge. This phenomenon is called straggling. Most of the time these “stragglers” emerge in small numbers and are quickly eaten by predators, and do not go on to sing, chorus (synchronized singing for the purpose of attracting females), mate, and lay eggs. Sometimes they emerge in numbers large enough to survive, chorus, and reproduce — this seems to have happened in the Chicago area in 2020. It is thought this is how new broods formed over the millennia — cicadas emerge 4 or 1 year early in significant numbers and form a new brood. When enough stragglers emerge to successfully reproduce it is called an acceleration.
So, is a new brood forming around Chicago? Is this due to climate change or localized “heat islands”? Will the progeny of these stragglers emerge in 13, 17 or 21 years? Lots of questions — but we’ll need to wait quite some time to answer them.
There is a precedence for Brood XIII cicadas straggling in the Chicago area:
In 1969 massive numbers of periodical cicadas emerged in the Chicago suburbs 1 (Williams, K.S. & Simon, C. 1995).
In 1986, another 4-year acceleration was observed in the Chicago area by Monte Lloyd 1.
In 2003, many people left observations on our forums. Observations were made in Glenview, Flossmoor, Riverside, Downers Grove, Homewood, Westmont, Oak Park, and Hinsdale. Here are some examples:
Magicicada emerging this evening
Date: Wednesday, Jun/4/2003
As I went for a walk this evening I noticed quite a few periodic cicadas emerging in the grass, crawling on the sidewalks and on the trunks of trees. This is not our year for the 17-year brood. We should not have them until 2007. Has anyone else in the Chicago area seen these cicadas? — Sue, Flossmoor, IL
Cicada singing
Date: Monday, Jun/9/2003
I heard the cicadas singing for the first time this morning after my walk. Now that I have my doors open I can hear them on and off. — Sue, Flossmoor, IL
In 2020 many people left comments on the Brood XIII page, emailed us (thanks Neil) and left sightings via the Cicada Safari app.
Looking at the latest map from Cicada Safari app data, it appears that cicadas from Brood V are emerging 4 years late. 4 year Stragglers! 21-year-old cicadas! Look around Akron, Ohio, eastern Ohio, western Pennsylvania, northern West Virginia.
The Forecast for 2025 is Brood XIV will emerge in Georgia, Indiana, Kentucky, Massachusetts, Maryland, North Carolina, New Jersey, New York, Ohio, Pennsylvania, Tennessee, Virginia, and West Virginia.
We will also get some stragglers from Brood I in Tennessee, Virginia, and West Virginia.
Magicicada Brood Chart
The Brood Chart features the names of the broods (Roman numerals), emergence years, cycle-length, straggler-years, species and states where they may emerge.
Emergences: 2031, 2014, 1997, 1980, 1963.
Cycle: 17-Year.
Stragglers: 2027 (-4), 2030 (-1)
Species: M. septendecim, M. cassini, M. septendecula.
States: IA, IL, MO
Emergences: 2036, 2019, 2002, 1985, 1968.
Cycle: 17-Year.
Stragglers: 2032(-4), 2035(-1)
Species: M. septendecim, M. cassini, M. septendecula.
States: OH, PA, WV and OK
Emergences: 2038, 2021, 2004, 1987, 1970.
Cycle: 17-Year.
Stragglers: 2034(-4), 2037(-1)
Species: M. septendecim, M. cassini, M. septendecula.
States: DE, GA, IL, IN, KY, MD, MI, NC, NJ, NY, OH, PA, TN, VA, WV, Washington
Emergences: 2041, 2024, 2007, 1990, 1973.
Cycle: 17-Year.
Stragglers: 2025(+1)
Species: M. septendecim, M. cassini, M. septendecula.
States: IA, IL, IN, MI, WI
Emergences: 2028, 2015, 2002, 1989, 1976.
Cycle: 13-Year.
Stragglers: 2027(-1), 2032(+4)
Species: M. tredecim, M. neotredecim, M. tredecassini, M. tredecula.
States: AR, IL, IN, KY, LA, MO, MS, TN
What specific day will they emerge?
Generally speaking, these cicadas will begin to emerge when the soil 8″ beneath the ground reaches 64 degrees Fahrenheit (Heath, 1968). A nice, warm rain will often trigger an emergence. They can emerge anytime from early April to early June. It all depends on the weather.
What should you look for before they emerge?
Chimneys / Turrets
Look for cicada chimneys a.k.a. turrets. These are structures cicadas build out of the soil, positioned above the hole where they will emerge.
Holes
Look for holes in the diameter of an adult’s finger near the root system of a tree. These are sure signs that cicadas will emerge in the area.
Cicadas Under Stones & Slates
You might discover some cicada nymphs while turning over stones or when performing landscaping chores.
This is a recently emerged nymph crawling up a tree. Note that its eyes are red.
Once cicadas nymphs have emerged from the ground, they will try to find a tree (or similar vertical surface), and then begin the process of shedding their old nymph skins (ecdysis), expanding their wings, and changing to their adult coloring. Watch this amazing transformation.
How to tell the difference between the seven Magicicada species:
Left to right: Magicicada cassini, Magicicada septendecula, Magicicada septendecim:
The first way is based on the Brood. Take a look at the Brood chart above, and see which species appear with the Brood.
There are 3 basic types of Magicicada: “‘Decims”, “‘Cassini” and “‘Deculas”.
Magicicada neotredecim Marshall and Cooley 2000. 13-year life cycle. Broods: XIX, XXIII.
Magicicada tredecim (Walsh and Riley, 1868). 13-year life cycle. Brood: XIX, XXII, XXIII.
Their songs are very similar, however, when M. neotredecim & M. tredecim emerge in the same location, M. neotredecim’s song takes a higher pitch. Sounds like “Pharaoh, Pharaoh!”.
Visual Appearance:
Male on left; Female on right.
M. neotredecim & M. septendecim have broad orange stripes with more orange than black on their abdomens.
M. tredecim, by comparison, have almost entirely orange abdomens.
M. septendecim cicadas also have an area of orange coloring between the eye and the wing (pronotal extension).
“Cassini” aka Dwarf Cicadas
There are two species in this category:
Magicicada cassini (Fisher, 1851). 17-year life cycle. Broods: I-V, VIII-X, XIII, XIV.
Magicicada tredecassini Alexander and Moore, 1962. 13-year life cycle. Broods: XIX, XXII, XXII.
Their songs are essentially identical:
M. cassini Call and Court:
Note how it makes a quick burst of sound, followed by some rapid clicks.
Visual Appearance:
Female on left; Male on right.
M. tredecassin & M. cassini cicadas have black abdomens with virtually no orange at all. Orange stripes are possible in the mid-west (important to note for Brood IV).
“Decula”
There are two species in this category:
Magicicada septendecula Alexander and Moore, 1962. 17-year life cycle. Broods: I-VI, VIII-X, XIII, XIV.
Magicicada tredecula Alexander and Moore, 1962. 13-year life cycle. Broods: XIX, XXII, XXIII.
Their songs are essentially identical:
M. tredecula Call:
Note the “tick, tick, tick” rhythm of the call.
Visual Appearance:
Female on left; Male on right.
M. septendecula & M. tredecula have stripes that feature more black than orange. Otherwise, they’re very similar to M. cassini.
How to figure out if they’re coming to your town?
Verify that they’re coming to your state. Check the Magicicada Brood Chart on this page.
Check Cicada Brood Maps linked from this page to see if they’re coming to your general area.
Check to see if they’re coming to your neighborhood. Good sources include:
Ask someone who lived there 17 (or 13) years before.
Old timers (hint: old timers usually call them locusts).
Check your local Library for old newspaper articles.
Check with a local college: contact the entomology, forestry, or agriculture-related departments.
Your local national, state, county, and town parks department (parks and rec). Some county parks departments plan events around cicada emergences.
When will they emerge?
They will emerge sometime in the Spring, for sure.
They typically emerge once the soil 8 inches (20 cm) below the surface gets to 64 degrees Fahrenheit (18 degrees Celcius). At that temperature, they will start digging their tunnels to the surface. After a couple of days with above-ground temperatures near the 80’s F, and after a good rain, they will emerge. Read this paper for more info: Thermal Synchronization of Emergence in Periodical “17-year” Cicadas (Homoptera, Cicadidae, Magicicada) by James Edward Heath, American Midland Naturalist, Vol. 80, No. 2. (Oct. 1968), pp. 440-448.
Cicadas in sunny areas of your yard will emerge before cicadas in shady areas.
Cicadas in the southernmost states will emerge before cicadas in the northern states.
Question: Why do I have cicadas in my neighborhood, but your chart indicates that I shouldn’t?
Answer: Some possibilities: 1) they are stragglers, periodical cicadas that emerge too soon or late, 2) they are not periodical cicadas but are a different North American species, 3) you live on a continent other than North America, in which case, try one of these pages, or 4) SURPRISE! The U.S. is a big place and some cicada populations have yet to be documented.
Question: Why don’t I have periodical cicadas in my area, but the information on your website indicates that I should?
Answer: Two possibilities: 1) they went extinct or otherwise died off in your area, or 2) they aren’t everywhere in a state – normally there are large gaps in their range.
Question: What are stragglers?
Answer:Stragglers can emerge 1 or 4 years early or 1 or 4 years late. Don’t be surprised if you see some periodical cicadas emerge earlier than planned this year. 17-year brood members are most likely to straggle 4 years early, and 13-year brood members are most likely to straggle 4 years late. Straggler probability chart.
Question: Are there other types of Periodical cicadas?
Answer: There are two known species of periodical cicadas that are not Magicicada . One lives in India and the other in Fiji.
Question: Why are there no Brood XI, XII, XV, or XVI?
Answer: Perhaps you’ve noticed there are no Broods XI (11), XII (12), XV (15), XVI (16), XVII (17), XVIII (18), XX (20), XXI (21), XXIV (24), etc. Don’t worry about that. They never existed or are extinct (XI, XXI).
Example Emergence Timeline
This is an example of a typical cicada emergence. The exact dates will depend on the weather and density of the emergence in your location. Hot weather means an early start and quicker finish to the season — cool weather means a later start and a protracted season.
In 2020, the main periodical cicada brood expected to emerge in the U.S. is Brood IX (9). Brood IX will emerge in southern West Virginia, western Virginia, and a small portion of north-western North Carolina. This we know for sure.
If you want to see where cicadas are being reported, try the Cicada Safari App is available for Android and Apple devices .
OK, here’s the point of this article:
Cicadas from other broods will also emerge this year in small numbers. When cicadas emerge early or late, they’re called stragglers. Don’t get hung up on the meaning of the word. If it makes you happy, call the ones that emerge early “precursors”, “pioneers”, or “heralds”.
Members of Brood XIX (19) are emerging in parts of North Carolina and Georgia, where Brood XIX is know to exist. There’s some discussion of this over on the Cicada Discussion, Science and Study Group on Facebook. You might see them in Alabama, Arkansas, Georgia, Illinois, Indiana, Kansas, Kentucky, Lousiana, Missouri, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, and Virginia.
The rest of Brood XIX will emerge in 2024. Here’s a map.
Members of Brood XIII (13) are likely to emerge 4 years early in Iowa, Wisconsin, Illinois, Indiana, and possibly Michigan.
The rest of Brood XIII emerge in 2024 (a big year for periodical cicadas). Here’s a map.
Some members of Brood X (10) should emerge 1 year early in Delaware, Georgia, Illinois, Indiana, Kentucky, Maryland, Michigan, North Carolina, New Jersey, New York, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia, and Washington D.C.
The rest of Brood X will emerge next year in 2021. Here’s a map.
Here’s a screen shot from the Cicada Safari app:
Within the app, you can zoom in to see where the cicadas are appearing. Here’s a “Live Map” of the sightings from the app.Pinch and zoom to get details.
Periodical cicada Brood IX (9) emerged in the spring of 2020 in North Carolina, Virginia and West Virginia. The last time this brood emerged was in 2003. It will emerge again in 2037.
Researchers need your help! If you see a cicada, please report it using the Cicada Safari App , available for Android and Apple phones.
Brood IX is interesting to researchers because it’s located very close to 5 other broods. In a normal year, researchers would be able to drive the roads of the area and map the location of the brood so we can get data as to where the broods intersect, but because of the current situation in the U.S., most if not all researchers will be able to travel — so we need you to let us know where they’re at. Read more on Cicadas @ UCONN (formerly Magicicada.org).
What, when, where, and why:
What:
Cicada insects with a 17-year life cycle.
Some people call them “locusts” but they’re really cicadas.
When: Typically beginning in mid-May and ending in late June. These cicadas will begin to emerge approximately when the soil 8" beneath the ground reaches 64 degrees Fahrenheit (Heath, 1968). A nice, warm rain will often trigger an emergence.
Other tips: these cicadas will emerge after the trees have grown leaves, and, by my own observation, around the same time Iris flowers bloom.
Where:
Virginia municipalities: Blacksburg, Bland, Callands, Christiansburg, Covington, Dry Pond, Ferrum, Martinsville, Roanoke, Salem, Vinton, and more.
Virginia counties: Allegheny, Bland, Franklin, Henry, Montgomery, Patrick, Pittsylvania, Roanoke.
North Carolina municipalities: Chestnut Hill, Ennice, Francisco, Hays, Kernersville, McGrady, Millers Creek, Mt Airy, North Wilkesboro, Purlear, Thurmond, Westfield, and more.
North Carolina counties: Ashe, Alleghany, Forsyth, Stokes, Surry, Wilkes.
West Virginia municipalities: Camp Creek, Elmhurst, Hinton, Jumping Branch, Spanishburg, and more.
West Virginia counties: Fayette, Greenbrier, Mercer, Monroe, Pocahontas, Summers.
A quick tip using data from the Cicada Safari app team:
Cicadas in the north-west areas are Brood IX (red). Cicadas south & east of that area (purple) are Brood XIX emerging early.
Not sure? Ask someone in your community who lived there 17 years ago.
Why:Why do they stay underground for 17-years? The prevailing research suggests they’ve evolved a long, 17-year lifecycle to avoid predators that can sync up with their lifecycle & emergence. Why are there so many?! Research suggests that their huge numbers allow them to overwhelm predators, so enough of them will live on to breed and perpetuate the brood.
Periodical cicada Brood XIII (13) emerged in the spring of 2024 in Iowa, Wisconsin, Illinois, Indiana, and Michigan (in one or two places). Brood XIII: rotten, but not forgotten. See you in 2041 (Yikes). Relive the memories: Gene Kritsky released a new book. See what people found iNaturalist: Flagging (Brown Leaves), Brood XIII, Massospora, and Blue and White eyes. Buy a shirt. Yes, Brood XIX also emerged in 2024, they did not overlap, but came close in the Springfield, Illinois area.
What, when, where, and why:
What:
Millions of these:
Cicada insects with a 17-year life cycle.
Some people call them “locusts” but they are cicadas.
When: Typically beginning in mid-May and ending in late June. These cicadas will begin to emerge approximately when the soil 8 inches beneath the ground reaches 64 degrees Fahrenheit. A nice, warm rain will often trigger an emergence.
Other tips: these cicadas will emerge after the trees have grown leaves, and, by my own observation, around the same time Iris flowers bloom.
Illinois places: Belvidere, Brookfield, Channahon, Chicago, Des Plaines River Trail, Downers Grove, Egermann Woods County Forest Preserve, Elmhurst, Flossmoor, Geneva, Glen Ellyn, Highland Park, Hinsdale, Homewood, La Grange, Lagrange Woods, Lake Forest, Lansing, Lincolnshire, Lisle, Lombard, MacArthur Woods Forest Preserve, Marseilles, McHenry, McKinley Woods, Morton Arboretum, Naperville, Northbrook, Ogden, Ottawa, Palos Heights, River Forest, River Grove, Romeoville, Ryerson Woods, Schiller Park, Thornton, Vernon Hills, Villa Park, Weaton, Western Springs, Westmont, Wonder Lake, and more.
Lake County Forest Preserve in Illinois: 1) A cicada exhibit opening at the Dunn Museum in Libertyville, IL on April 27th. 2) Cicadas of Lake County on 5/2. 3) Celebrating Cicadas on 5/16. 4) On Sunday, June 9th, they plan to hold CicadaFest at Ryerson Woods. Insects, and of course, cicadas will be featured.
Why:Why do they stay underground for 17 years? The prevailing research suggests they have evolved a long lifecycle allowing them to avoid predators that would sync up with their lifecycle & emergence. Why are there so many?! Research suggests that their huge numbers allow them to overwhelm predators, so enough of them will live on to breed and perpetuate the brood.
Smaller than M. neotredecim & M. tredecim. Orange stripes on its abdomen, through not as much as M. neotredecim & M. tredecim. Its chorus sounds like a ticking clock. Very similar to the 17-year M. septendecula.
Video Playlist
Playlists contain multiple videos found on YouTube.
Descriptions, Colors: personal observations from specimens or photos from many sources. Descriptions are not perfect, but may be helpful.
Tribe information comes from: MARSHALL, DAVID C. et al.A molecular phylogeny of the cicadas (Hemiptera: Cicadidae) with a review of tribe and subfamily classification.Zootaxa, [S.l.], v. 4424, n. 1, p. 1—64, may 2018. ISSN 1175-5334. Available at: https://www.biotaxa.org/Zootaxa/article/view/zootaxa.4424.1.1
Notes:
Some descriptions are based on aged specimens which have lost some or a lot of their color.
Descriptions, Colors: personal observations from specimens or photos from many sources. Descriptions are not perfect, but may be helpful.
Tribe information comes from: MARSHALL, DAVID C. et al.A molecular phylogeny of the cicadas (Hemiptera: Cicadidae) with a review of tribe and subfamily classification.Zootaxa, [S.l.], v. 4424, n. 1, p. 1—64, may 2018. ISSN 1175-5334. Available at: https://www.biotaxa.org/Zootaxa/article/view/zootaxa.4424.1.1
Notes:
Some descriptions are based on aged specimens which have lost some or a lot of their color.
Its abdomen is black. Its chorus sounds like hissing static. It is smaller than M. neotredecim and M. tredecim. It is very similar to the 17-year M. cassinii species.
Descriptions, Colors: personal observations from specimens or photos from many sources. Descriptions are not perfect, but may be helpful.
Tribe information comes from: MARSHALL, DAVID C. et al.A molecular phylogeny of the cicadas (Hemiptera: Cicadidae) with a review of tribe and subfamily classification.Zootaxa, [S.l.], v. 4424, n. 1, p. 1—64, may 2018. ISSN 1175-5334. Available at: https://www.biotaxa.org/Zootaxa/article/view/zootaxa.4424.1.1
Notes:
Some descriptions are based on aged specimens which have lost some or a lot of their color.
